The British explorer said that the Paon-1X exploration well in the CI-103 licence had found good quality light oil.
The successful result in the Ivory Coast followed disappointment in the country in April when the company drilled a dry hole.
Tullow operates the huge Jubilee oil field in Ghana, which is the first commercial oil development in the country. The firm has been pushing its hunt for oil westwards in the hope of discovering more oil off the Ivory Coast.
“The discovery of light oil in our first well in CI-103 extends the proven play for oil westwards from our successes in Ghana and is encouraging for our future exploration efforts elsewhere in this licence,” said Tullow’s exploration director Angus McCoss.
Tullow owns a 45 per cent stake in the CI-103 licence and is partnered with US explorer Anadarko.