Modulation transfer function (MTF) velocity mismatch feature for time delay integration (TDI) complementary metal-oxide-semicoductor (CMOS) area image sensors is studied. A model of MTF velocity mismatch is proposed. The effecting factors such as accumulation stage, pixel size, lens magnification, line cycle, motor velocity are analyzed. A TDI algorithm for CMOS area image sensor is applied to achieve time delay integration. The TDI-CMOS system is developed based on a FPGA development board. The experimental results show that fMTF increases 50% by 8 accumulation stage compared to CMOS area sensor, when the intensity is 3 lx and velocity mismatch M(ΔV/V) is less than 2. The fMTF at the Nyquist frequency decreases 10% by 8 accumulation stage, when the velocity mismatch M(ΔV/V)=2. When the velocity mismatch M(ΔV/V)=10, the fMTF decreases 35%.