Mr Singh joined the BJP ahead of Prime Minister Narendra Modi's rally in Barmer.
Former BJP MP Manvendra Singh, son of former Union minister Jaswant Singh, returned to the party on Friday following a five-year stint with the Congress.
Mr Singh, who had switched to Congress in October 2018, joined the BJP ahead of Prime Minister Narendra Modi's rally in Barmer. He also shared the stage with other leaders of the BJP during the PM's rally.
"Today I rejoined the BJP family and party workers in the presence of Prime Minister Narendra Bhai Modi at Adarsh Stadium in Barmer. We are all committed to realising the public welfare policies of Prime Minister Narendra Modi and the resolution of 'Vikshit Bharat'," he said in a Facebook post.
Mr Singh was elected as the BJP MLA from Barmer's Sheo assembly constituency in December 2013.
When the BJP denied a ticket to Jaswant Singh, who then contested the Lok Sabha election as an independent and lost, Manvendra Singh turned rebel and campaigned against the party's candidate in support of his father.
Manvendra Singh was suspended from the party ahead of the 2018 assembly elections.
He joined the Congress, which gave him a ticket for the Jhalrapatan assembly seat against the then-chief minister Vasundhara Raje. He lost the election.
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