A scroll compressor may include a compressor chamber, a back pressure chamber, a first intermediate pressure hole, a second intermediate pressure hole, a third intermediate pressure hole, a back pressure switching unit configured to selectively connect the first intermediate pressure hole and the back pressure chamber or the second intermediate pressure hole and the back pressure chamber, a capacity variable unit configured to selectively open and close a capacity variable passage, and a mode switching unit provided outside of the casing and configured to control opening and closing operations of the back pressure switching unit and the capacity variable unit. This may simplify the structure of the back pressure switching unit and the mode switching unit, thereby maintaining compactness of the compressor while installing the back pressure switching unit inside of the casing, and thus, operation reliability of the mode switching unit may be secured and maintenance facilitated.