An outdoor unit comprising: a refrigerant pipe for the circulation of a refrigerant; a housing that houses the refrigerant pipe, wherein the housing includes an upper panel, a front panel, a right side panel, a left side panel, a back panel, and a bottom panel; a sound-proof box (10, 30) that is housed in the housing and surrounds a compressor being configured to cause the refrigerant to be circulated; a connection valve (8, 9) connected to an end of the refrigerant pipe and an external pipe; and a valve bed that fixes the connection valve (8, 9), characterized in that the right side panel is divided into a front side part of the right side panel connected to the front panel and a back side part of the right side panel; a part of the right side of the front panel and the front side part of the right side panel constitute a service panel that is detachable; the valve bed having one end fixed to an inner surface of the back side part of the right side panel of the housing and the other end fixed to a side plate (10c, 30c) of the sound-proof box (10, 30) that is closer to the right side panel to which the one end of the valve bed is fixed than is another one of the side plates (10c, 30c, 10e), wherein a front surface plate and an upper surface plate of the sound-proof box (10, 30) is detachable, wherein detachment of the service panel allows for detachment of the upper surface plate and the front surface plate of the sound-proof box and in the detached state of the front surface plate and the upper surface plate the other end remains fixed to the right side plate of the sound-proof box, wherein the front panel includes a blowing grille for sucking air into the heat pump outdoor unit wherein holes are formed at a lower part of the front panel for insertion of an extension pipe. a refrigerant pipe for the circulation of a refrigerant; a housing that houses the refrigerant pipe, wherein the housing includes an upper panel, a front panel, a right side panel, a left side panel, a back panel, and a bottom panel; a sound-proof box (10, 30) that is housed in the housing and surrounds a compressor being configured to cause the refrigerant to be circulated; a connection valve (8, 9) connected to an end of the refrigerant pipe and an external pipe; and a valve bed that fixes the connection valve (8, 9), characterized in that the right side panel is divided into a front side part of the right side panel connected to the front panel and a back side part of the right side panel; a part of the right side of the front panel and the front side part of the right side panel constitute a service panel that is detachable; the valve bed having one end fixed to an inner surface of the back side part of the right side panel of the housing and the other end fixed to a side plate (10c, 30c) of the sound-proof box (10, 30) that is closer to the right side panel to which the one end of the valve bed is fixed than is another one of the side plates (10c, 30c, 10e), wherein a front surface plate and an upper surface plate of the sound-proof box (10, 30) is detachable, wherein detachment of the service panel allows for detachment of the upper surface plate and the front surface plate of the sound-proof box and in the detached state of the front surface plate and the upper surface plate the other end remains fixed to the right side plate of the sound-proof box, wherein the front panel includes a blowing grille for sucking air into the heat pump outdoor unit wherein holes are formed at a lower part of the front panel for insertion of an extension pipe.