An electric lock, comprising a main lock which comprises a housing accommodating a driving assembly and a first connecting member, the driving assembly comprising a driving member and a rotating shaft which is rotatably arranged on the housing, a first threaded portion being arranged at one end of the rotating shaft, a second threaded portion adapted to the first threaded portion being arranged at one end of the first connecting member while a third threaded portion being arranged at the other end of the first connecting member, and a secondary lock which comprises a first sleeve, an elastic member and a second connecting member, the elastic member being arranged in the first sleeve and having one end abutting against the second connecting member, a fourth threaded portion adapted to the third threaded portion being arranged on the second connecting member, the second connecting member being able to move along the axis of the first sleeve; wherein the driving member drives, via the rotating shaft, the first connecting member to move along the axis of the rotating shaft and to screw in the second connecting member, characterized in that the second connecting member is rotatably arranged in the first sleeve and wherein the secondary lock further comprises a manual unlocking assembly comprising a second sleeve and an unlocking member; the second sleeve is arranged on the peripheral wall of the first sleeve and perpendicular to the first sleeve; at the junction of the first sleeve and the second sleeve, a hollow region of the second sleeve is communicated with a hollow region of the first sleeve; a fifth threaded portion is arranged on the unlocking member, and the unlocking member is rotatably arranged in the second sleeve; a sixth threaded portion adapted to the fifth threaded portion is arranged on the second connecting member. a main lock which comprises a housing accommodating a driving assembly and a first connecting member, the driving assembly comprising a driving member and a rotating shaft which is rotatably arranged on the housing, a first threaded portion being arranged at one end of the rotating shaft, a second threaded portion adapted to the first threaded portion being arranged at one end of the first connecting member while a third threaded portion being arranged at the other end of the first connecting member, and a secondary lock which comprises a first sleeve, an elastic member and a second connecting member, the elastic member being arranged in the first sleeve and having one end abutting against the second connecting member, a fourth threaded portion adapted to the third threaded portion being arranged on the second connecting member, the second connecting member being able to move along the axis of the first sleeve; wherein the driving member drives, via the rotating shaft, the first connecting member to move along the axis of the rotating shaft and to screw in the second connecting member, characterized in that the second connecting member is rotatably arranged in the first sleeve and wherein the secondary lock further comprises a manual unlocking assembly comprising a second sleeve and an unlocking member; the second sleeve is arranged on the peripheral wall of the first sleeve and perpendicular to the first sleeve; at the junction of the first sleeve and the second sleeve, a hollow region of the second sleeve is communicated with a hollow region of the first sleeve; a fifth threaded portion is arranged on the unlocking member, and the unlocking member is rotatably arranged in the second sleeve; a sixth threaded portion adapted to the fifth threaded portion is arranged on the second connecting member.