Wheelsets are the main components of movement and force of trains. Wheelset fault is one of the main causes that threaten the safety of trains. The rapid and accurate measurement of the geometric parameters and defects of wheelset can effectively reduce the accident rate and the maintenance cost, and provide the scientific decision-making basis for the design and manufacture of wheel and rail. It has become the research focus in the relevant fields in the world. In this paper, based on a brief description of the development of wheelset geometric parameter detection, our work on the dynamic measurement of geometric parameters and defects in the past 20 years is introduced. We first proposed the principle for quantitatively measuring the wheel tread abrasion and circumferential wear using a parallelogram mechanism, and then put forward the method for accurately measuring the tread diameter using one-dimensional laser displacement sensors and the method for measuring geometric parameters and defects using multi-line lasers. We also developed several different types of wheelsets on-line measurement systems that have been applied to the railway site. The development trend of wheelset inspection is discussed in the end of this paper.