"I have quit Congress after being influenced by Narendra Modi's call," Patnaik, who is often described as the "Ganjam Tiger", said while senior BJP leader Biswabhusan Harichandan welcomed him and his family members into the party fold.
Patnaik, who was a minister in the council of ministers of both Biju Patnaik and Naveen Patnaik, had quit BJD in 2004 and joined Congress before the general elections.
He was the minister of finance and agriculture in the BJD government from 2000 to 2004.
Patnaik's wife Kumudini was elected to Lok Sabha from Aska and his daughter Anita is a new entrant in politics.
Maharaj of Kalahandi Udit Pratap Deb and his wife Padma Manjari Deo also formally joined the BJP.
Meanwhile, former deputy mayor of Bhubaneswar Municipal Corporation (BMC) BJP's Urmila Mohapatra joined the BJD in presence of Chief Minister Naveen Patnaik.