The solar wind originates from the solar atmosphere. It undergoes heating when it propagates in the interplanetary space. It is unclear what heats the solar wind, a frontier problem in space physics. The solar wind is commonly in the state of turbulence, and the turbulence energy is believed to be an important source of the solar wind heating. However, two key questions remain, i.e., what is the specific medium heating the solar wind and what is the microscopic mechanism of the heating. This paper reviews the history of the studies on the solar wind heating problem, with the focus on domestic works about solar wind ion-scale turbulence and its heating. This paper also raises several questions to be solved and interesting topics on the solar wind heating in the future.