The Africa-focused player has completed drilling the Mlinzi Mbali-1 well on Block 7 but found the targets to be water-bearing, it said on Thursday.
The main target was a structural crest in the Lower Cretaceous channel complex with secondary targets in the Upper Cretaceous and Jurassic.
Although Ophir said both Cretaceous targets were intercepted, it made no reference to the Jurassic target.
Shares in Ophir were down around 7% at 9am in London on Thursday.
The well was drilled in around 2600 metres of water, with the planned depth of around 5650 metres.
Ophir previously said that success with the well would derisk the total resource potential within the overall Mlinzi Channel complex, which is estimated to be in excess of 20 Tcf.
Chief executive Nick Cooper said: “Mlinzi Mbali-1 was the first of a series of high-impact, high-risk wells that will be drilled by Ophir through 2014.
“This frontier well disappointingly did not encounter live hydrocarbons.
“However it is the deepest stratigraphic test offshore Tanzania and will provide crucial information that will be integrated into our interpretation of the potential of Block 7 and the wider deep-water basins of Tanzania.”
The well was drilled with the Deepsea Metro I drillship, which will now head off to Kenya to drill the Sunbird prospect on Block L10A for UK major BG Group.
*Eoin O’Cinneide, Upstreamonline