Consolidated net profit at Rs 280 crore in April- September was higher than Rs 243 crore net profit in the same period of the previous fiscal, the company said in a statement.
OVL is unlisted company and is not required by law to provide quarterly earning statement.
Standalone net profit, however, fell 72.3 per cent to Rs 134 crore "mainly due to forex movements and provisioning against exploratory carry finance," the company said without providing details.
Oil production in the first half of current fiscal rose 33.6 per cent to 4.815 million tonnes after OVL got higher volumes from Russia's Vankor field where it increased its stake to 26 per cent.
Gas output rose 17.6 per cent to 2.2 billion cubic meters.
The production in H1 was higher "mainly due to acquisition of additional 11 per cent stake in Vankorneft project in Russia in October 2016."
The firm previously held 15 per cent stake in the Russia's second-biggest oil producing field.
OVL said it had raised finances by way of bridge loan to acquire 11 per cent shares in Vankor in October 2016.
"The bridge loan has been successfully replaced in April 2017 with $500 million and 38 billion Japanese Yen syndicated term loan facilities at competitive prices from reputed international banks," it added.
OVL in 2016 bought 15 per cent stake in Vankor from Russian national oil firm Rosneft for $1.268 billion. It bought an additional 11 per cent for $930 million.
Vankor is Russia's second largest field by production and accounts for 4 percent of Russian production. The daily output from the field is around 400,000 barrels per day of crude oil (BOPD) on an average and OVL's share of daily oil production from Vankor is about 104,000 BOPD.