A high-speed current mode sense amplifier for Spin Torque Transfer Magnetic Random Access Memory (STT MRAM) is proposed. The sense amplifier is designed in a 0.18 μm CMOS technology, and 1.8 V supply voltage. The resistance values of high state is 2132 Ω, low state is 1215 Ω, and reference state is 1512 Ω, respectively. The proposed sense amplifier decreases the dropping rate of input bias. In particular, it can reduce the sensing time and the power-delay-product (PDP). In addition, the proposed sense amplifier has higher driving ability.