To provide a hermetic motor-driven compressor which can restrain noise and vibration from increasing when an imbalanced mass increases due to an enlargement of the internal volume of a cylinder during use of hydrocarbon as coolant.

A hermetic container 21 has a bottom surface consisting of two or three spherical surface parts 21a, 21b having different radii of curvature. Legs 26 are welded to the spherical surface parts 21a and 21b, having spherical surface parts of the same shape at that of the spherical surface parts 21a and 21b. With this arrangement, the rigidity of the hermetic container 21 is higher so that noise transmitted therefrom is lowered. Further, a ring-like elastic member 31 is inserted between a snub bar 30 and a stay 29 so that vibration from a compression element can hardly be directly transmitted from the snub bar 30 to the stay 29, thereby reduce noise can be reduced during operation of the compressor.