The party has promised to create one crore jobs in five years, if voted to power in Karnataka.
Rahul Gandhi, 47, released the manifesto a day after a mid-air scare on his flight to Karnataka. The Congress has called for an investigation,alleging "intentional tampering" of the aircraft. The plane landed at Hubli airport but according to the complaint, only after two aborted attempts.
Karnataka Chief Minister Siddaramaiah, veteran leaders Veerappa Moily, Mallikarjun Kharge and other leaders too were present at TMA Pai Convention Hall in the coastal city.
The 44-page booklet has a prominent image of Rahul Gandhi and the tricolor on its cover.
Rahul Gandhi has a packed day of campaigning day ahead. After the manifesto's release, he addressed a gathering on Bantwal, 25 km from Mangaluru. He will be visiting a math or seminary in Dakshina Kannada district and will later address public gatherings in Kodagu and Mysuru.
In Karnataka, the Congress is facing a stiff battle from the BJP which is trying to reclaim the state where it formed a government in 2008. Karnataka is one of the only three states ruled by the Congress.
Polling in the high-stakes elections will take place on May 12 and counting of votes will take place three days later.