The present invention relates to a wind turbine (10), which includes a plurality of blades (141, 142, 143), a micro inertial measurement unit (20), and a monitoring system (303). The micro inertial measurement unit (20) is installed on each blade (141, 142, 143), and is configured to sense a plurality of detection parameter signals at corresponding installation positions. The monitoring system (303) is configured to monitor an operating state of the plurality of blades (141, 142, 143), and the monitoring system (303) includes a signal processing unit (305), a signal analyzing unit (307), and a fault evaluating unit (309). The signal processing unit (305) obtains a processing parameter signal through calculation based on the plurality of detection parameter signals (313). The signal analyzing unit (307) analyzes each analysis parameter signal to obtain a fault estimation signal. The analysis parameter signal is selected from the plurality of detection parameter signals (313) and the processing parameter signal, and each fault estimation signal is used to estimate whether a corresponding blade works in a fault state. The fault evaluating unit (309) is configured to evaluate, based on a plurality of fault estimation signals, whether a corresponding blade fails or a probability that the corresponding blade fails. The present invention further discloses a method (1000) for evaluating a health state of a wind turbine blade (10).