A muscle detector, a massage apparatus and a method for detecting a muscle are provided. The muscle detector includes a detection component attached to a part to be detected and used to detect a muscle hardness change at the part to be detected and obtain a signal indicating a value of the muscle hardness change at the part to be detected, and a data processing component used to calculate the value of the muscle hardness change at the part to be detected according to the signal indicating the value of the muscle hardness change at the part to be detected, compare the value of the muscle hardness change at the part to be detected with a preset value, and issue a detection to-be-processed instruction in response to a determination that the value of the muscle hardness change at the part to be detected is greater than the preset value.
