Upali Tennakoon, editor of the Rivira newspaper had been attacked by persons who arrived in two mortor cycles, a staff member said.
He had not been critically injured.
The deputy editor and defence analyst of The Nation the English newspaper of the same company, Keith Noyahr was abducted, assaulted and later released last year.
Noyahr then left the country. The ownership of the newspaper firm then changed hands.
The attack comes after Lasantha Wickremetunga, the editor of The Sunday Leader newspaper was killed.
Media rights bodies have named Sri Lanka as one of the most dangerous places in the world for journalists after Iraq.