----

|   | 1.         I have reviewed this annual report on Form 10-K of Aceto Corporation      (the “Registrant”); |
|--------|------------------------------------------------------------------------------------------------------------------------------------------|

|   | 2.         Based on my knowledge, this report does not contain any untrue statement      of a material fact or omit to state a material fact necessary to make the      statements made, in light of the circumstances under which such statements      were made, not misleading with respect to the period covered by this      report; |
|--------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|   | 3.         Based on my knowledge, the financial statements, and other financial      information included in this report, fairly present in all material      respects the financial condition, results of operations and cash flows of      the Registrant as of, and for, the periods presented in this      report; |
|--------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|   | 4.   The      Registrant’s other certifying officer and I are responsible for      establishing and maintaining disclosure controls and        procedures      (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and      internal control over financial reporting       (as      defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the Registrant      and have: |
|--------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|  a) |   | designed such      disclosure controls and procedures, or caused such disclosure controls and      procedures to be                        |
|----------|--------|--------------------------------------------------------------------------------------------------------------------------------------------|
|     |   | designed under our      supervision, to ensure that material information relating to the      Registrant, including its                    |
|     |   | consolidated      subsidiaries, is made known to us by others within those entities,      particularly during the period in                |
|     |   | which      this report is being prepared;                                                                                                  |
|     |   |                                                                                                                                       |
|  b) |   | designed such      internal control over financial reporting, or caused such internal control      over financial reporting                |
|     |   | to  be      designed under our supervision, to provide reasonable assurance regarding      the reliability of financial          |
|     |   | reporting and the      preparation of financial statements for external purposes in accordance      with U.S. generally                    |
|     |   | accepted accounting      principles; and                                                                                                   |
|     |   |                                                                                                                                       |
|  c) |   | evaluated the      effectiveness of the Registrant’s disclosure controls and procedures and      presented in this report            |
|     |   | our conclusions      about the effectiveness of the disclosure controls and procedures, as of      the end of the period                   |
|     |   | covered by this      report based on such evaluation; and                                                                                  |
|     |   |                                                                                                                                       |
|  d) |   | disclosed in this      report any change in the Registrant’s internal control over financial      reporting that occurred            |
|     |   | during the      Registrant’s most recent quarter (the registrant’s fourth fiscal quarter      in the case of an annual report) |
|     |   | that has materially      affected, or is reasonably likely to materially affect, the Registrant’s      internal control over         |
|     |   | financial reporting;      and                                                                                                              |

|   | 5.         The Registrant’s other certifying officer and I have disclosed, based on      our most recent evaluation of internal control over financial reporting,      to the Registrant’s auditors and the audit committee of the Registrant’s      board of directors (or persons performing the equivalent      functions): |
|--------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|  a) |   | all significant      deficiencies and material weaknesses in the design or operation of      internal control over financial                                                                    |
|----------|--------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
|     |   | reporting which are      reasonably likely to adversely affect the Registrant’s ability to record,      process, summarize and report financial information; and                          |
|     |   |                                                                                                                                                                                            |
|  b) |   | any fraud, whether      or not material, that involves management or other employees who have a      significant role in the Registrant’s internal control over financial      reporting. |