A CMOS circuit with difference interface in which the difference input pole contains 4 PMOS transistors, namely M3, M4, M5 and M6; 5 NMOS transistors, namely M1, M2, M7, M8 and M9. These transistors jointly constitute NMOSFET input CMOS difference primary amplification circuit, wherein M1 and M2 are a pair of NMOS transistors, constituting geminate transistors; M3 and M5, M4 and M6, as well as M7 and M8 are double-scale mirror image current source as the load for M1 and M2; the M7 and M8 pair of current mirrors simultaneously converts double-end output into single-end output. M9 provides the direct current, i.e. tail current required by difference electric work; primary amplification circuit is linked with a secondary amplification circuit that is comprised of a PMOS transistor and a NMOS transistor Ma, wherein Ma is amplifier tube and Mb is the loading tube for Ma; the grid electrode level of the loading tube is connected with ground GND; the secondary amplification circuit is linked with the buffer output comprising two directors.