Abstract: An integrated circuit design method includes: classifying flipflops arranged around a macro based on a netlist of a integrated circuit incorporating the flipflops and the macro; and generating a flipflop-replaced netlist from the netlist. In classifying the flipflops, a flipflop which is connected to an input terminal of the macro directly or through an input-side logic cone and operated on the same clock signal as the macro is classified as a control type, and a flipflop which has a data output connected to an input terminal of the macro directly or through the input-side logic cone and operated on a different clock signal is classified as a hold type.