The actor-turned-politician also said Tejashwi would be a "major player" in the next Assembly polls in Bihar.
"I am amazed at the maturity and poise that Tejashwi displays while answering tough questions. He has a bright future. He will definitely emerge as a force to reckon with," he told a news channel.
The comments of Mr Sinha, who represents the Patna Sahib Lok Sabha constituency, come close on the heels of his meeting with jailed RJD supremo Lalu Prasad in Ranchi on Saturday.
This meeting was followed by a visit, a day later, to the residence of former Chief Minister Rabri Devi whom he met in the presence of her sons Tejashwi and Tej Pratap.
"The precision with which Tejashwi speaks reminds me of NCP chief Sharad Pawar in his hey day," Mr Sinha remarked.
Replying to a query, he said, "Undoubtedly Tejashwi would be a major player in the next assembly polls in Bihar. I cannot say whether he will be in a direct fight with Chief Minister Nitish Kumar, who is also my dear friend. But even Nitish said the young man has a long political career ahead."
Mr Sinha was referring to Mr Kumar's intervention in the Assembly yesterday wherein the chief minister had advised his former deputy to exercise restraint while raising, on the floor of the House, matters relating to communal tensions.
Mr Sinha, who has been critical of his own party and the Narendra Modi government for quite some time, said he was upset over not getting an invitation for the Bihar Diwas celebrations held last week.
"The Bihari Babu was not invited to Bihar Diwas, for reasons we all know and I need not elaborate upon. So I thought it would be a good idea to meet my old friend Lalu who is a mass leader," Mr Sinha said.
"Bihari Babu" is one of the sobriquets by which Mr Sinha is known.
"Thereafter, on coming to Patna I met his family members and told them that Lalu was doing fine. It was a great reunion after a long time," he added.
Mr Sinha had visited a Ranchi hospital, where RJD supremo Lalu Prasad is admitted, accompanied by local Congress MP and former Union minister Subodh Kant Sahay.
Lalu Prasad has been serving sentence after being convicted in fodder scam cases. He was admitted to the hospital on March 17 after he fell ill at the Birsa Munda Jail in Ranchi.
Mr Sinha, however, parried questions about his future political moves as well as queries relating to the allegations levelled against his party over the recent spurt in communal tension in Bihar.
"We shall talk about these things later," he said.