The present disclosure relates to a buckle for connecting a strap and a respirator harness including the same. In particular, according to one aspect of the present disclosure, a buckle for connecting a strap including a coupler configured to extend from one position, a strap connector at which a strap connecting hole is formed, wherein the strap connecting hole is connected to a strap which is connected to a mask body, and a hooking portion connected to the one position and including a surface configured to face the coupler, wherein a tap of a helmet or a tap of a head cradle is accommodated between the coupler and the hooking portion so that a position thereof is fixed, and a respirator harness including the same are provided.