Exhibit 8.1

List of Significant Subsidiaries of United Microelectronics Corporation



|                                                    |  |                              |  |                                                |        |  
|--------------------------------------------------- |  | ---------------------------- |  | ---------------------------------------------- | ------ | -
|Company                                             |  | Jurisdiction ofIncorporation |  | Percentage ofOwnership 
as ofDecember 31, 2016 |       
|UMC Group (USA)                                     |  | U.S.A.                       |  |                                                | 100.00 | %
|United Microelectronics (Europe) B.V.               |  | The Netherlands              |  |                                                | 100.00 | %
|UMC Capital Corp.                                   |  | Cayman Islands               |  |                                                | 100.00 | %
|TLC Capital Co., Ltd.                               |  | Taiwan, R.O.C.               |  |                                                | 100.00 | %
|UMC New Business Investment Corp.                   |  | Taiwan, R.O.C.               |  |                                                | 100.00 | %
|Green Earth Limited                                 |  | Samoa                        |  |                                                | 100.00 | %
|Fortune Venture Capital Corp.                       |  | Taiwan, R.O.C.               |  |                                                | 100.00 | %
|UMC Investment (Samoa) Limited                      |  | Samoa                        |  |                                                | 100.00 | %
|Unitruth Investment Corp.                           |  | Taiwan, R.O.C.               |  |                                                | 100.00 | %
|UMC Capital (USA)                                   |  | U.S.A.                       |  |                                                | 100.00 | %
|ECP Vita Pte. Ltd.                                  |  | Singapore                    |  |                                                | 100.00 | %
|Soaring Capital Corp.                               |  | Samoa                        |  |                                                | 100.00 | %
|Unitruth Advisor (Shanghai) Co., Ltd.               |  | China                        |  |                                                | 100.00 | %
|Tera Energy Development Co., Ltd.                   |  | Taiwan, R.O.C.               |  |                                                | 100.00 | %
|United Microchip Corporation                        |  | Cayman Islands               |  |                                                | 100.00 | %
|Nexpower Technology Corp.                           |  | Taiwan, R.O.C.               |  |                                                | 67.54  | %
|Wavetek Microelectronics Corporation                |  | Taiwan, R.O.C.               |  |                                                | 78.47  | %
|Everrich Energy Investment (HK) Limited             |  | China                        |  |                                                | 100.00 | %
|Everrich (Shandong) Energy Co., Ltd.                |  | China                        |  |                                                | 100.00 | %
|Unistars Corp.                                      |  | Taiwan, R.O.C.               |  |                                                | 82.76  | %
|NPT Holding Limited                                 |  | Samoa                        |  |                                                | 67.54  | %
|NLL Holding Limited                                 |  | Samoa                        |  |                                                | 67.54  | %
|SocialNex Italia 1 S.R.L.                           |  | Italy                        |  |                                                | 67.54  | %
|UMC (Beijing) Limited                               |  | China                        |  |                                                | 100.00 | %
|Wavetek Microelectronics Investment (Samoa) Limited |  | Samoa                        |  |                                                | 78.47  | %
|Wavetek Microelectronics Corporation (USA)          |  | U.S.A.                       |  |                                                | 78.47  | %
|Best Elite International Limited                    |  | British Virgin Islands       |  |                                                | 91.08  | %
|Infoshine Technology Limited                        |  | British Virgin Islands       |  |                                                | 91.08  | %
|Oakwood Associates Limited                          |  | British Virgin Islands       |  |                                                | 91.08  | %
|Hejian Technology (Suzhou) Co., Ltd.                |  | China                        |  |                                                | 91.08  | %
|UnitedDS Semiconductor (Shandong) Co., Ltd.         |  | China                        |  |                                                | 91.08  | %
|United Semiconductor (Xiamen) Co., Ltd.             |  | China                        |  |                                                | 26.79  | %
|UMC Group Japan                                     |  | Japan                        |  |                                                | 100.00 | %
|UMC Korea Co., Ltd.                                 |  | Korea                        |  |                                                | 100.00 | %
|Omni Global Limited                                 |  | Samoa                        |  |                                                | 100.00 | %
|United Microtechnology Corporation (California)     |  | U.S.A.                       |  |                                                | 100.00 | %
|United Microtechnology Corporation (New York)       |  | U.S.A.                       |  |                                                | 100.00 | %
|Sino Paragon Limited                                |  | Samoa                        |  |                                                | 100.00 | %
|UMC Technology Japan Co., Ltd.                      |  | Japan                        |  |                                                | 100.00 | %