The invention discloses a three-dimensional measuring method and a measuring apparatus thereof. The method includes: A, setting a laser sensor and an optical sensor on an unmanned flight platform; B, measuring three-dimensional information of ground features through the laser sensor to obtain laser point cloud data; C, acquiring texture and color information of the ground features through the optical sensor to obtain a plurality of photos; D, obtaining flight parameters of the unmanned flight platform through a position and orientation system; E, synchronizing the times of the laser point cloud data, the photos and the flight parameters to the same time reference; F, obtaining the flight path of the unmanned flight platform through calculation, fusing the corresponding laser point cloud data and the photos, and forming fusion point cloud data; and G, correspondingly processing the fusion point cloud data to obtain target output data. According to the three-dimensional measuring apparatus, the equipment size is small, the measuring precision is high, and the apparatus can play a great role in various application fields.