In the present radio frequency device, a radio frequency circuit part and a transmission line are disposed on the top surface of a circuit board on the surface of which a ground pattern is provided, and a metal shielding cap is fixed to the circuit board so as to cover the radio frequency circuit part and the transmission path. The metal shielding cap includes: a top plate disposed above the radio frequency circuit part and substantially parallel to the circuit board; a grounded side wall being provided so as to hang down from a part of an edge of the top plate, having a spring property and being joined to the ground pattern of the circuit board, and a side wall is open except for the grounded side wall.