Abstract In a proton therapy system based on cyclotrons, a kicker magnet is an essential equipment to perform fast beam switch within 100 μ s level during energy modulation and spot scanning procedures. This paper gives a systematic view related to the design and technical considerations of a fast kicker applied to HUST-PTF. From the layout and physical requirement of the kicker, a comparative study on the static/dynamic magnetic field with two type of core materials is performed, and a MnZn ferrite core is chosen finally. Technical considerations including the structure design, the topology design of the power supply, and the method for dynamic field measurement are introduced as well.