The present invention discloses a plant point cloud acquisition, registration, and optimization method based on a time of flight (TOF) camera, which includes the following steps: (1) placing a to-be-tested plant on a turntable, adjusting a view angle of the TOF camera, and aligning the TOF camera with the to-be-tested plant; (2) turning on the turntable so that it rotates automatically, and enabling the TOF camera to acquire point cloud data of the to-be-tested plant at intervals; (3) performing real-time preprocessing on each frame of point cloud data acquired by the TOF camera; (4) performing registration and optimization on every two adjacent frames of point cloud data, and then integrating the data to obtain complete plant point cloud data; and (5) using statistical filtering to remove the discrete noise in the plant point cloud data obtained in the registration and optimization process to obtain final point cloud data.