Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F. 

Form 20-F ___X___ Form 40-F _______

Indicate by check mark whether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes _______ No___X____

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Tests confirm light oil discovery in the Santos Basin

(Rio de Janeiro, September 20, 2007). – PETRÓLEO BRASILEIRO S/A - PETROBRAS, [Bovespa: PETR3/PETR4, NYSE: PBR/PBRA, Latibex: XPBR/XPBRA, BCBA: APBR/APBRA], a Brazilian international energy company, announces that the formation tests carried out for the second Tupi area well, 3-BRSA-496-RJS (3-RJS-646), have been wrapped-up and proved the Southwardly extension of the light oil discovery (28^o API) by well 1-BRSA-369A-RJS (1-RJS-628A), in deep Santos Basin waters.

These tests confirmed the light oil discovery made via the pioneering well, as announced to the market on July 11 2006. The Tupi area is located in Block BM-S-11, which is operated by Petrobras (65%) in a consortium with BG Group (25%) and Petrogal – GALP ENERGIA (10%) as partners.

In a clarification announced last August 29^th, Petrobras informed the drilling procedures for this second well were concluded on June 24, but that the company would only have more information after the tests had been finished, which occurred now.

The second well is located 9.5 km southeast of the pioneering discovery well, at a depth of 2,166 meters, some 286 kilometers off the southern coast of the city of Rio de Janeiro (view the figure below).

The test carried out in the well suggests a production of some 2,000 barrels of oil and 65,000 cubic meters of natural gas per day, with flow being limited due to the test’s operating installations and for safety reasons.

The Consortium will give continuity to the activities and investments foreseen in the Assessment Plan developed for this light oil (28º API) field, as approved by the NPA on 02/27/2007. The main purpose of these activities is to check the oil- and gas-bearing reservoir’s dimensions and characteristics in order to ensure the economic viability of developing an oil and gas production project in this block. More conclusive data about the discovery’s potential will only be known after the other assessment process phases have been finalized.

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   www.petrobras.com.br/ri/english
Contacts: PETRÓLEO BRASILEIRO S. A. – PETROBRAS
Investor Relations Department I E-mail: petroinvest@petrobras.com.br
Av. República do Chile, 65 – 22^nd floor - 20031-912 - Rio de Janeiro, RJ I Tel.: 55 (21) 3224-1510 / 9947

This document may contain forecasts that merely reflect the expectations of the Company’s management. Such terms as “anticipate”, “believe”, “expect”, “forecast”, “intend”, “plan”, “project”, “seek”, “should”, along with similar or analogous expressions, are used to identify such forecasts. These predictions evidently involve risks and uncertainties, whether foreseen or not by the Company. Therefore, the future results of operations may differ from current expectations, and readers must not base their expectations exclusively on the information presented herein.

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   www.petrobras.com.br/ri/english
Contacts: PETRÓLEO BRASILEIRO S. A. – PETROBRAS
Investor Relations Department I E-mail: petroinvest@petrobras.com.br
Av. República do Chile, 65 – 22^nd floor - 20031-912 - Rio de Janeiro, RJ I Tel.: 55 (21) 3224-1510 / 9947

This document may contain forecasts that merely reflect the expectations of the Company’s management. Such terms as “anticipate”, “believe”, “expect”, “forecast”, “intend”, “plan”, “project”, “seek”, “should”, along with similar or analogous expressions, are used to identify such forecasts. These predictions evidently involve risks and uncertainties, whether foreseen or not by the Company. Therefore, the future results of operations may differ from current expectations, and readers must not base their expectations exclusively on the information presented herein.

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This press release may contain forward-looking statements. These statements are statements that are not historical facts, and are based on management's current view and estimates offuture economic circumstances, industry conditions, company performance and financial results. The words "anticipates", "believes", "estimates", "expects", "plans" and similar expressions, as they relate to the company, are intended to identify forward-looking statements. Statements regarding the declaration or payment of dividends, the implementation of principal operating and financing strategies and capital expenditure plans, the direction of future operations and the factors or trends affecting financial condition, liquidity or results of operations are examples of forward-looking statements. Such statements reflect the current views of management and are subject to a number of risks and uncertainties. There is no guarantee that the expected events, trends or results will actually occur. The statements are based on many assumptions and factors, including general economic and market conditions, industry conditions, and operating factors. Any changes in such assumptions or factors could cause actual results to differ materially from current expectations.

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