Mane joined NCP in the presence of Maharashtra Deputy Chief Minister Ajit Pawar at a function in party office here this morning.
He said Youth Congress President Rajeev Satav, who hails from Hingoli, a district in Marathwada region, was functioning in an "autocratic" manner. "I was feeling suffocated in the Congress and was being ignored."
"I decided to join NCP as this is a party which has pro-development outlook," Mane told reporters.
Ajit said NCP, headed by his uncle and Union Minister Sharad Pawar, would treat Mane with honour and respect, and utilise his potential in Marathwada in Central Maharashtra.
NCP, which shares power with Congress in Maharashtra and at the Centre, has netted leaders from the two saffron parties, Shiv Sena and BJP, over the past few weeks.
Panditanna Munde, elder brother of senior BJP leader Gopinath Munde, joined NCP last week, and his son (Gopinath's nephew) Dhananjay, too, is likely to follow suit.
Shiv Sena Lok Sabha member from Kalyan Anand Paranjpe has indicated intentions to join the Sharad Pawar-led outfit.
Paranjpe shared stage with Sharad Pawar a few days ago and lashed out at the Shiv Sena leadership.