Abstract: This paper presents a statistical analysis of the internal accuracy of the fixed-point deformation observation data of Wuzhishan deformation station from January 2016 to December 2021. The internal accuracy of the station’s water pipe tiltmeter and indium tile rod extensometer is good. The probability that the internal accuracy of the two components of the broadband tiltmeter reaches the excellent index is only 50%. Since January 2020, the internal accuracy quality of the observation data has been decreasing, resulting in the low quality of the observation data. The important condition for improving the internal accuracy quality of data is to ensure the continuous rate of observation data. Therefore, it is urgent to improve the operational level of station personnel and to ensure the necessary spare parts.