Aiming at the technical difficulties in the rapid detection and reconstruction of three-dimensional micro-nano devices that are difficult to achieve both high precision and high speed, this paper proposes a structured light detection method based on time-domain phase shift technology. The measured light is modulated by a spatial light modulator, and the time-domain phase shift technology is further employed to realize the detection and reconstruction of three-dimensional micro-nano devices. Compared with the traditional structured light detection method, this technology uses the spatial light modulator to measure the phase shift while the sample is scanned axially, so as to ensure the measurement accuracy and improve the measurement efficiency. By analyzing the measurement data, this method can quickly realize three-dimensional shape detection and reconstruction, and the measurement accuracy can be better than 10 nm.