Rep. George V. Hansen (R-Idaho), indicted last week by a federal grand jury on four counts of filing false financial disclosure statements, pleaded not guilty in U.S. District Court yesterday to what he called "phony and trumped up charges."

The seven-term congressman entered the plea in a brief hearing before Judge Joyce Hens Green, who released him on his personal recognizance and set a June 20 trial date.

The grand jury charged that Hansen neglected to report four major financial transactions--including three involving Texas billionaire Nelson Bunker Hunt. The indictment was the first issued under the 1978 Ethics in Government Act for allegedly falsifying financial disclosure statements that congressmen are required by law to file with the House Ethics Committee.

Hansen's lawyer, Frank Campbell, told Green he would be filing a motion to dismiss the indictment and would argue that the indictment was a violation of constitutional separation of powers between the Congress and the executive branch.

Talking to reporters after the 15-minute hearing, Hansen said his plea was "innocent, loud and clear." The 52-year-old congressman said he had "done things right . . . . We're prepared to prove this and that the Justice Department is dead wrong on this matter."

Campbell, citing "pressing demands" on Hansen from legislative business, asked the judge not to require Hansen to appear at pretrial hearings. Green denied the request. "I would expect there is nothing more important on his calendar at this time" than the charges against him, Green said.