An interpolation circuit, includes a bias generating module, a load module consisting of a current source sub-module and a load resistance sub-module, first and second clock control modules, and an output module. The first clock control module includes a first input sub-module, a first source terminal negative feedback sub-module, a first multiplex switch sub-module and a first multiplex current sink sub-module. The bias generating module includes first, second and third FETs, and a bias current terminal. The current source sub-module includes fourth and fifth FETs. The load resistance sub-module includes first and second resistors. The first input sub-module includes sixth and seventh FETs. The first source terminal negative feedback sub-module includes a third resistor and a first capacitor. The first multiplex switch sub-module includes first and second groups of switches. The first multiplex current sink sub-module includes first and second groups of FETs. An interpolation system is further provided.