Two Republican senators including Paul S. Trible of Virginia have introduced legislation to outlaw the use of computers to facilitate dealings by child pornographers, child molesters and pedophiles.

According to the FBI, the use of computers by child molesters or pedophiles to communicate with one another and catalog their activities is increasing.

Trible, who introduced the bill along with Sen. Jeremiah Denton of Alabama, said, "The use of computers to deal in child pornography is extremely alarming. So, too, is the prospect that pedophiles are exchanging information on their victims."

Trible cited the arrest of a Virginia Beach man last month on charges of distributing obscene material involving juveniles. The man was a computer programmer and systems analyst, and he used a computer to find those interested in child pornography, according to the prosecutor's office in Virginia Beach.

Jack D. Smith, general counsel of the Federal Communications Commission, recently told a Senate subcommittee chaired by Denton that his agency would endorse legislation such as the pending bill.

But Justice Department officials said the bill "raises serious constitutional questions" because the material to be banned often is not, in and of itself, obscene or indecent.

One practice Trible hopes to prohibit is the transmission of information about victims of one child molester to other child molesters. He cited a case in which a computer network listed children by sex, race, hair and eye color, type of sexual act performed and other particulars. The mailing list was hundreds of feet long, according to Trible.

"It is particularly worrisome when the molester knows the name and address of the child and can exchange this information by the secretive means of computer transmission," said Trible. "This worsens the risk that an abused child will become the target of another pedophile."

But Justice Department officials told Denton's subcommittee on security and terrorism that legislation seeking to ban the transmission of descriptive information about juveniles would probably run into serious constitutional First Amendment problems.