To provide a sensor element capable of easily performing a frequency adjustment with high accuracy while achieving the simplification of a manufacturing process, and a highly-reliable sensor device and electronic apparatus each having the sensor element.

A sensor element 2 comprises: a base part 31; detecting vibration arms 33, 34 and driving vibration arms 35 to 38 which extend from the base part 31; piezoelectric elements 41 to 44, 51 to 58 which are provided on the detecting vibration arms 33, 34 and the driving vibration arms 35 to 38 and which have first electrode layers, second electrode layers, and piezoelectric layers provided between the first electrode layers and the second electrode layers; and mass adjustment parts 61 to 66 which are provided on the detecting vibration arms 33, 34 and the driving vibration arms 35 to 38 and which have mass adjustment layers formed of the same material as the piezoelectric layers.