To provide an antenna for microwave detonation detonatable with minimized microwave output that is a detonation method needing no detonating cord, and an explosive capsule using it.

This antenna is adapted so that an antenna formed in a fiber shape by use of carbon fiber is irradiated with microwave to heat the antenna itself to high temperature, whereby the antenna is detonated. This explosive capsule comprises the antenna disposed within a capsule filled with explosive or blasting powder so as to make contact with the explosive or blasting powder, whereby the capsule is detonatable by microwave irradiation.