Provided is an electric actuator, including: a driving motor (2); a motion conversion mechanism (6) configured to convert a rotary motion of the driving motor (2) to a linear motion; a boot (27) configured to prevent entry of a foreign substance into the motion conversion mechanism (6); and a boot cover (31) arranged so as to cover an outer side of the boot (27), wherein the boot cover (31) is formed integrally with an exterior case (8) of the electric actuator, and wherein a boot mounting member (30) having the boot (27) mounted thereto is mounted to an inner side of the boot cover (31).