A piezoelectric MEMS sensor and a related device is disclosed, applied to scenarios such as a terminal, a smart acoustic system, a wireless Bluetooth headset, an active noise reduction headset, a notebook computer, and an automobile industry, including a substrate including a sound entry channel and at least one cantilever. The cantilever includes a first region and a second region that are connected to each other. The first region includes a first side face and a second side face, the first side face is a side face that is of the first region and that faces a target face, and the target face is a face that is of the cantilever and that is connected to the substrate. An included angle between the first side face and the second side face is greater than or equal to 90 degrees and less than 180 degrees.