Sen. Herman Talmadge (D-Ga.) and his former top aide are trading charges about the handling of nearly $13,000 in government funds that the aide put in a Washington bank account after submitting reportedly false expense claims.

The former aide, Daniel Minchew, said through his attorney yesterday that he had submitted the vouchers and deposited the funds at Talmadge's direction in 1973 and 1974. But Minchew - now a member of the International Trade Commission - denied taking any of the money and said he thought the funds were passed on to the senator and his family, according to Bruce Morris, his Atlanta attorney.

Talmadge issued a statement denying that Minchew acted on his orders and saying he didn't get any of the money either. He did so in response to inquiries from The Washington Star, which broke the story yesterday.

Talmadge said he referred the matter to the Justice Department in mid-July after an audit showed that the two checks in question had gone through Riggs National Bank in Washington rather than his usual account in Atlanta.

The Minchew clash is the latest in a series of allegations about the handling of government funds in Talmadge's office.

A knowledgeable Justice Department official said yesterday that an investigation has been started but it is too early to fix blame.

The Senate Ethics Committee which is investigating Talmadge's financial dealings is expected to interview Minchew early next week his lawyer said.

Minchew says he put the money - $10,605 in June 1973 and $2,290 in March 1974 - in a Riggs account other than his own. His lawyer declined to identify who controlled the account.

The Senate funds were paid to reimburse Talmadge for official expenses. The vouchers prepared by Minchew claimed money for postage and operation of the senator's Atlanta office. The Star quoted a source as saying no justification for the expenses had been found.

Minchew was Talmadge's administrative assistant from mid-1971 to late 1974, when he took the $50,000-a-year post on the trade commission.