The collapse marks the second such incident in a week. Another tunnel collapse last Sunday also killed a member of the terror group Islamic Jihad's armed wing.
The July 10 collapse occurred in the northern Gaza Strip, the Al-Quds Brigades said in a statement, without providing further details.
It identified the terrorist killed as Ibrahim Hassan Al-Masri, 28, of Al-Quds's northern command.
Over the last several months there have been several similar incidents in Gaza. In early April, five diggers were killed in a tunnel collapse at the city of Rafah, located in southern Gaza on the border with the Sinai Peninsula.
That incident was already the eleventh tunnel cave-in over a period of several months.
Hamas has been busily reconstructing its terror tunnel network breaching into Israeli territory, and after one of the collapses, some media reports speculated that a secret Israeli weapon - and not heavy rains - was responsible for the cave-ins.
Back in February the IDF warned that Hamas appears to be focusing its efforts on one central tunnel breaching deep into sovereign Israel to facilitate attacks on civilians. Reportedly 1,000 Hamas terrorists are working on the major tunnel.