He said Jaitley should be replaced by someone who can handle the Finance Ministry "properly".
He said Jaitley had been repeatedly amending the GST but insisted that the tax regime would not work.
"Jaitely as the Finance Minister did not apply his brain when he prepared and implemented the GST. This is evident the way he has been tinkering it time and again. Even today some changes have been made. But any patchwork will not work. GST needs an overhaul."
Sinha asked Modi to set up a high-level committee headed by economist Vijay Kelkar to study GST and suggest remedial measures.
Earlier, Sinha rubbished Modi's claim that demonetization and GST were successful, saying both exercises had actually failed.
"Notebandi and GST failed as their objectives were not fulfilled. None of the black money has returned to the banks" after Rs 1,000 and Rs 500 notes were scrapped in November last year, he said.
"But as usual the central government has been telling lies to claim that it was a success," he said at a function organised by rebel JD-U leader Uday Narain Choudhary.
Accusing the Modi government of not being serious about fighting corruption, he asked why a probe had not been ordered into the business dealings of Bharatiya Janata Party President Amit Shah's son Jay Shah.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)