A force detector includes a first base part, a second base part, and a pressure detection unit provided between the first base part and the second base part and including a piezoelectric element that outputs a signal in response to an external force, wherein the pressure detection unit has a first member having a portion in contact with the first base part, a second member having a portion in contact with the second base part, and a third member connecting the first member and the second member, a first longitudinal elastic modulus of at least a part of the first member is lower than a third longitudinal elastic modulus of the third member, and a second longitudinal elastic modulus of at least a part of the second member is lower than the third longitudinal elastic modulus of the third member.