A radar device includes radar transmission and receiving circuits. The radar transmission circuit transmits one or more transmission signals, each having a transmission period Tr. The radar receiving circuit receives one or more reflected signals in which the transmission signals are reflected by an object and estimates a direction of the object based on the reflected signals. The radar transmission circuit includes Nt transmission antennas. A control circuit sets a transmission gap period between a first and second periods, with the transmission gap period being a period during which the transmission signals are not transmitted. The first period is equal to an integral multiple of a period Np, the period Np is equal to or more than Nt times the transmission period Tr, and the second period is set after the first period and is equal to an integral multiple of the period Np.