a casing;

a cylinder that is disposed in an inner space of the casing to define a compression space;

a roller that is disposed on a rotational shaft to be rotatable in the inner space of the cylinder and eccentric with respect to a center of the compression space to have a contact point close to an inner circumferential surface of the cylinder; and

at least one vane that is slidably inserted into at least one vane slot disposed in the roller, respectively, to be rotatable along with the roller,

wherein the roller includes at least one bypass passage through which spaces on both sides of the contact point based on a rotational direction of the roller periodically communicate with each other and;

wherein an angle between ends of the at least one bypass passage is smaller than or equal to an angle between a discharge completion point of the at least one vane and the contact point.