In this paper, fast current mode control (FCMC) boost converter is proposed and verified by circuit simulation. The proposed FCMC boost converter consists of the conventional current mode control (CMC) boost converter and a differentiator which is used to sense the change of inductor current according to the load current. The proposed circuit has a minimum of 2 times faster response speed than the conventional CMC boost converter. The proposed FCMC boost converter is designed and verified by Cadence Spectre using 0.18㎛ 1-poly 6-metal process technology. The simulation results show that the output voltage is 20V in 10V input voltage while output ripple is below 156mV.