By comparing the sunshine durations obtained by Jordan sunshine recorder and the two automatic observation sunshine detectors (FS-RZ1 sunshine sensor and FS-ST series automatic solar tracker, abbreviated as FS-RZ1 and FS-ST respectively) during May-August2018 in Huzhou, Changxing, and Deqing, Zhejiang, China, and statistically analyzing the relative difference between the daily sunshine durations of the three detectors, it is found that the observation values of the three detectors are highly correlated . In comparison, there is a high degree of credibility of sunshine duration obtained by the automatic observation detector, and the sunshine durations of FS-RZ1 and FS-ST are generally lower than those of Jordan sunshine recorder. The correlation of FS-ST and Jordan sunshine recorder can reach about 0.99, which is slightly higher than that of FS-RZ1 and Jordan sunshine recorder. This difference may be related to whether the Deqing station observers have the awareness to do a comparison of artificial and automatic observations. The analysis also shows that the detection environment, local weather conditions and the difference in the operational quality of station observers are the main factors that affect the relative difference between artificial and automatic sunshine duration.