Spasm is a common complication of stroke with high morbidity and a high disability rate. Spasticity continues to impair the patient’s motor function, and symptoms such as muscle shortening and joint deformity may occur, which seriously affects the patient’s physical and mental health. Systemic therapy is a key part to control spasticity clinically. However, systematic treatment is conducted on the basis of proper assessment. The tools for assessing spasticity are divided into two categories: subjective and objective, and the subjective assessment tools mainly include some scales, which are subjectively assessed and judged by the therapist. Objective methods mainly include electrophysiology testers, ultrasonic measurement techniques, robots, three-dimensional motion analysis systems, isokinetic muscle strength testers, etc. This paper analyzes and summarizes the methods of post-hemiplegic spasticity assessment through a literature review, reviews the advantages, disadvantages and practicability of various assessment methods, and puts forward prospects for future research directions.