Unidentified militants hurled a grenade at a patrolling party of the CRPF in the main town of Kulgam, about 70 kms from here, the official said.
Quoting preliminary information, he said the grenade blast left Assistant Sub-Inspector Rajinder Singh injured.
The whole area was immediately cordoned off and a hunt was launched to nab the attackers, the official said.
The injured officer was shifted to a hospital.
No militant outfit has so far claimed responsbility for the incident.
Earlier on Saturday, Chief Minister Mehbooba Mufti met Home Minister Rajnath Singh to discuss the law and order situation in the state, especially security to Amarnath pilgrims, even as she blamed "external forces" for creating trouble in the state.
Seven pilgrims were killed by militants in Anantnag district while returning from the Amarnath cave shrine on Monday.
"Kashmir issue is not a law and order problem. It is happening because of external forces. The ongoing fight is a handiwork of external forces and now unfortunately China is also trying to meddle into it," Mehbooba told reporters emerging from the meeting.
Four districts of the state -- Pulwama, Kulgam, Shopian and Anantnag -- have been on the boil since the killing of Hizbul Mujahideen commander Burhan Wani in an encounter with security forces on July 8, 2016.
The unrest has resumed since the April 9 bypoll to the Srinagar Lok Sabha seat.