Abstract: This paper compares and analyzes the observation environment, installation and operation of the DSQ-type water pipe inclinometer of the Hohhot reference seismic station and Baotou seismic station, and the observation accuracy, stability, continuity, and reliability of observation data from 2015 to 2017. Contrastive analysis, quality evaluation, and systematic calculation and analysis were performed using multiple processing methods. The quality index of the mean square error of the M₂ wave tidal factor is obtained by using the Venidikov harmonic analysis, and the intrinsic quality accuracy was obtained. The Chebyshev polynomial was used to fit and analyze the annual observation data to obtain the relative noise level of the instrument, and the two indicators were compared and analyzed. It is of great practical significance to make a correct understanding and objective evaluation of the precursory observation system of the station’s topographical change observation data, and is beneficial to the future earthquake precursory and prediction research.