**Exhibit  12.1**

**302  CERTIFICATION**

I, Mario Valcarce,  certify that:

1.   I    have reviewed this annual report on Form 20-F of Enersis S.A.;

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 company as of, and for,  the periods presented in this report;

4.   The company’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)*)  for the company 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 company, 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)   [Paragraph      omitted pursuant to SEC Release Nos. 33-8238 and 34-47986] 

 (c)    Evaluated      the effectiveness of the company’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 company’s internal control over financial      reporting that occurred during the period covered by the annual report      that has materially affected, or is reasonably likely to materially affect,    the company’s internal control over financial reporting; and 

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

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(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 company’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 company’s internal control over financial    reporting.

| Date: June      9, 2005 |   | /s/      Mario Valcarce      Mario Valcarce      Chief Executive Officer |
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