The observed data in recent years indicated that, some changes of tidal characteristics have taken place in south Zhejiang province. In order to study its variation trends, the tidal features were analyzed based on the data observed in Wenzhou, Rui'an and Aojiang stations in recent 60 years by the Mann-Kendall test and the Bernaola-Galvan(B-G) segmentation algorithm. The results showed that a great change has taken place to the tidal characteristics in south Zhejiang province. Both the average high tidal level and tidal range increased, while the average low tidal level decreased gradually, meanwhile the flood-tide duration increased and the ebb-tide duration shortened. The change amplitudes of the tidal characteristics at the three stations were different. The smallest variation of the average high tidal level was at Wenzhou station, and the biggest variations of the average low tidal level and tidal range wre at Wenzhou station. But the biggest variation of the flood-tide duration was at Aojiang station. This analysis showed that the time of mutation of the tidal characteristics agreed with the period of increasing human activities such as sand excavation and tideland reclamation. This meant that human activities are the main factor which caused the tidal characteristics change.