An outdoor unit of an air conditioner comprising: a compressor to compress a refrigerant; a condenser to condense the refrigerant discharged from the compressor; a control device which includes electronic parts to control the outdoor unit, the electronic parts becoming heated while operating; and a cooling unit in contact with a heat generating part of the electronic parts to cool the heat generating part which is heated while operating, wherein the cooling unit comprises: a first heat radiation member installed to be in contact with the heat generating part; a refrigerant pipe which extends through the first heat radiation member and which enables a refrigerant to flow through the refrigerant pipe; and a second heat radiation member coupled with the first heat radiation member to transfer heat from the first radiation member, and in contact with outdoor air flowing into the control device, wherein the control device includes a case which provides a space for the electronic parts in the control device, and the second heat radiation member extends from one side of the first heat radiation member to an outer side of the case, and wherein the first heat radiation member is manufactured in a die casting process of injecting a molten metal into a mould with the refrigerant pipe located inside the mould. a compressor to compress a refrigerant; a condenser to condense the refrigerant discharged from the compressor; a control device which includes electronic parts to control the outdoor unit, the electronic parts becoming heated while operating; and a cooling unit in contact with a heat generating part of the electronic parts to cool the heat generating part which is heated while operating, wherein the cooling unit comprises: a first heat radiation member installed to be in contact with the heat generating part; a refrigerant pipe which extends through the first heat radiation member and which enables a refrigerant to flow through the refrigerant pipe; and a second heat radiation member coupled with the first heat radiation member to transfer heat from the first radiation member, and in contact with outdoor air flowing into the control device, wherein the control device includes a case which provides a space for the electronic parts in the control device, and the second heat radiation member extends from one side of the first heat radiation member to an outer side of the case, and wherein the first heat radiation member is manufactured in a die casting process of injecting a molten metal into a mould with the refrigerant pipe located inside the mould. a first heat radiation member installed to be in contact with the heat generating part; a refrigerant pipe which extends through the first heat radiation member and which enables a refrigerant to flow through the refrigerant pipe; and a second heat radiation member coupled with the first heat radiation member to transfer heat from the first radiation member, and in contact with outdoor air flowing into the control device, wherein the control device includes a case which provides a space for the electronic parts in the control device, and the second heat radiation member extends from one side of the first heat radiation member to an outer side of the case, and wherein the first heat radiation member is manufactured in a die casting process of injecting a molten metal into a mould with the refrigerant pipe located inside the mould.