A base plate for a heat sink as well as a heat sink and an IGBT module having the same are provided. The base plate includes: a base plate body, including a body part; and a first surface layer and a second surface layer disposed respectively on two opposing surfaces of the body part; and N pins disposed on the first surface layer and spaced apart from one another, each pin having a first end fixed on the first surface layer and a second end configured as a free end, in which the first surface layer and the N pins are configured to contact a coolant, an area of a first portion of the first surface layer contacting the coolant is denoted as S1, and an area of a second portion of the first surface layer contacting each pin is denoted as S2, in which 180≤S1/S2≤800, and 300≤N