The arrests come after a ceasefire took hold last week along the Line of Control in Jammu and Kashmir, following cross-border killings that threatened to unravel a fragile peace process.
Pakistan's Maritime Security Agency (MSA) arrested the Indian fishermen and seized six boats, alleging they were 40 nautical miles inside Pakistani waters.
"MSA officials on Sunday seized some six Indian fishing boats and arrested 27 crew members for poaching inside Pakistani waters and handed them to us today," police official Mohammad Hashim told AFP.
Pakistan and India frequently arrest each other's fishermen on charges of violating their respective zones in the Arabian Sea.
Pakistan has over 200 Indian fishermen in its jails and around 125 Pakistani fishermen are in Indian prisons.
India and Pakistan have fought three wars since independence in 1947, two of them over Kashmir, which is divided by a heavily militarised Line of Control but which both countries claim in full.