WASHINGTON (AP) _ The Supreme Court will not be going to Philadelphia on Sept. 17 to help celebrate the 200th anniversary of the signing of the Constitution, Chief Justice William H. Rehnquist confirmed Friday.

''Applicable statutes require that the court conduct its business only in Washington, D.C.,'' Rehnquist said in declining what he said was a gracious invitation for the nine justices to take part in the bicentennial celebration in Philadelphia.

We The People, the organization running the Philadelphia celebration, asked the court and Congress to hold special sessions there to help commemorate the Constitution's signing.

Rehnquist said the justices decided at a recent private conference to turn down the invitation, noting the court rejected a similar invitation to take part in the bicentennial celebration of the Declaration of Independence in 1976.

''Members of the court are making individual plans to participate in various bicentennial events'' this year, Rehnquist added.

Retired Chief Justice Warren E. Burger is heading a national commission planning the Constitution's 200th anniversary celebration.

The Associated Press reported Jan. 3 that Burger was not getting all the cooperation he had hoped for from his former colleagues in celebrating the bicentennial. Sources said then that the justices had decided in private not to sit in Philadelphia on Sept. 17.