Exhibit 21

Tellabs, Inc. and Subsidiaries

Subsidiaries of the
Registrant

as of January 1, 2010



|                                                             |  |                                             
|------------------------------------------------------------ |  | --------------------------------------------
|Name                                                         |  | State or Other Jurisdiction of Incorporation
|Tellabs Operations, Inc.                                     |  | Delaware                                    
|Tellabs International, Inc.                                  |  | Illinois                                    
|Tellabs de Colombia Ltda                                     |  | Colombia                                    
|Tellabs South Africa (S.A.) (Proprietary) Limited            |  | South Africa                                
|Tellabs Communications Canada Ltd.                           |  | Canada                                      
|Tellabs do Brasil, Ltda.                                     |  | Brazil                                      
|Tellabs H.K. Limited                                         |  | Hong Kong                                   
|Tellabs Pty Limited                                          |  | Australia                                   
|Tellabs International de Mexico S.A. de C.V.                 |  | Mexico                                      
|Tellabs Asia Pacific Pte Ltd                                 |  | Singapore                                   
|Tellabs (Thailand) Co., Ltd.                                 |  | Thailand                                    
|Tellabs Korea Limited                                        |  | Korea                                       
|Tellabs India Private Limited                                |  | India                                       
|Tellabs Communications International Limited                 |  | China                                       
|Tellabs Communication Technologies (Shanghai) Limited        |  | China                                       
|Tellabs K.K.                                                 |  | Japan                                       
|Tellabs de Venezuela, S.A.                                   |  | Venezuela                                   
|Tellabs Communications (Malaysia) Sdn. Bhd.                  |  | Malaysia                                    
|Tellabs (Malaysia) Sdn. Bhd. (49% joint venture)             |  | Malaysia                                    
|Tellabs Philippines, Inc.                                    |  | Philippines                                 
|Tellabs Holdings B.V.                                        |  | The Netherlands                             
|Tellabs Enterprises B.V.                                     |  | The Netherlands                             
|Tellabs Oy                                                   |  | Finland                                     
|Kiinteisto Oy Mestarinkaarre                                 |  | Finland                                     
|Kiinteisto Oy Sinimaentie 6                                  |  | Finland                                     
|Tellabs Denmark A/S                                          |  | Denmark                                     
|Tellabs Communications (India) Private Limited               |  | India                                       
|Kring  Tellabs India Private Limited                        |  | India                                       
|Tellabs Holdings Limited                                     |  | Ireland                                     
|Tellabs Limited                                              |  | Ireland                                     
|Tellabs Research Limited                                     |  | Ireland                                     
|Tellabs EMEA Holdings Limited                                |  | Ireland                                     
|Tellabs AB                                                   |  | Sweden                                      
|Tellabs Holdings SA (Proprietary) Limited                    |  | South Africa                                
|Tellabs SAS                                                  |  | France                                      
|Tellabs Italia S.r.l.                                        |  | Italy                                       
|Tellabs Netherlands B.V.                                     |  | The Netherlands                             
|Tellabs Poland Sp. z o.o.                                    |  | Poland                                      
|Tellabs Southern Europe s.a. Sociedad Unipersonal (Spain)    |  | Spain                                       
|Tellabs Deutschland GmbH                                     |  | Germany                                     
|Tellabs Austria Vertriebs GmbH                               |  | Austria                                     
|Tellabs Norway AS                                            |  | Norway                                      
|Tellabs U.K. Ltd.                                            |  | United Kingdom                              
|Tellabs Communications UK Limited                            |  | United Kingdom                              
|E. Coherent Communications Systems Limited                   |  | United Kingdom                              
|Tellabs FZ-LLC                                               |  | Dubai                                       
|EMEA TEL LAMP (EMEA TEL LAB)                                 |  | Greece                                      
|Telecommunications Single Partner Limited Liability Company  |  |                                             
|Tellabs North America, Inc.                                  |  | Delaware                                    
|Tellabs Petaluma, Inc.                                       |  | Delaware                                    
|Tellabs Vienna, Inc.                                         |  | Delaware                                    
|Advanced Fibre Technology Communications (Hong Kong) Limited |  | Hong Kong                                   
|Hangzhou AFTEK Communication Company, Ltd.                   |  | China                                       



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|                                                        |  |                    
|------------------------------------------------------- |  | -------------------
|Advanced Fibre Communications (HK) Limited              |  | Hong Kong          
|AFC Foreign Sales Corporation                           |  | U.S. Virgin Islands
|Tellabs Bedford, Inc.                                   |  | Delaware           
|AccessLan India                                         |  | India              
|Advanced Fibre Communications (India) Private Limited   |  | India              
|Tellabs International GmbH                              |  | Switzerland        
|Advanced Fibre Communications Mexico S. de R.L. de C.V. |  | Mexico             
|Advanced Fibre Communications International Limited     |  | Cayman Islands     
|AFC Harris Multimedia Communications Private Limited    |  | Mauritius          
|AFC Harris Multimedia Communications Limited            |  | India              
|Tellabs Mexico, Inc.                                    |  | Delaware           
|Tellabs de Mexico, S.A. de C.V.                         |  | Mexico             
|Tellabs TG, Inc.                                        |  | Delaware           
|Tellabs Transport Group Inc.                            |  | Quebec             
|Tellabs Nevada Holdings Corporation                     |  | Nevada             
|Tellabs Treasury Holdings Corporation                   |  | Nevada             
|Tellabs Equity Holdings Corporation                     |  | Nevada             
|Tellabs Securities Holdings Corporation                 |  | Nevada             
|Tellabs Reston, Inc.                                    |  | Delaware           
|Tellabs San Jose, Inc.                                  |  | Delaware           
|WiChorus, Inc.                                          |  | Delaware           
|Wichorus Design and Development Private Limited         |  | India              
|WICHORUS (PRIVATE) LIMITED                              |  | Pakistan