A refrigeration apparatus including a refrigerant circuit in which a vapor compression refrigeration cycle is performed, the refrigeration apparatus comprising: a compressor that is provided in the refrigerant circuit and whose operating frequency is capable of being changed; an evaporator that is provided in the refrigerant circuit and is configured to perform heat exchange by causing refrigerant circulated by the compressor to evaporate in a heating operation; a condenser that is provided in the refrigerant circuit and is configured to perform heat exchange by causing the refrigerant circulated by the compressor to condense in the heating operation; a switching mechanism that is provided in the refrigerant circuit and is configured to switch the flow of the refrigerant in the refrigerant circuit when switching between the heating operation using the condenser and a defrost operation that defrosts the evaporator, an expansion mechanism that is provided in the refrigerant circuit and is configured to cause the refrigerant flowing between the evaporator and the condenser to expand so that the pressure of the refrigerant is reduced, and a control unit configured to control the refrigeration apparatus, characterized in that the control unit is configured to control the operating frequency of the compressor and an opening degree of the expansion mechanism during the defrost operation such that a high-pressure value of the refrigerant circuit in the defrost operation is lower than a high-pressure value of the refrigerant circuit in the heating operation, and in that the control unit is configured to control the refrigeration apparatus such that an end-of-defrost frequency decrease rate being a rate of decrease in the operating frequency of the compressor in the defrost operation is set faster than a normal frequency decrease rate being a rate of decrease in the operating frequency of the compressor in the heating operation, wherein the operating frequency of the compressor is lowered at the end-of-defrost frequency decrease rate to a calm operation frequency (Fmin), which is an operating frequency equal to or greater than a predetermined value, and the compressor is arranged and configured to maintain the calm operation frequency, without stopping, when reverting from the defrost operation to the heating operation. a compressor that is provided in the refrigerant circuit and whose operating frequency is capable of being changed; an evaporator that is provided in the refrigerant circuit and is configured to perform heat exchange by causing refrigerant circulated by the compressor to evaporate in a heating operation; a condenser that is provided in the refrigerant circuit and is configured to perform heat exchange by causing the refrigerant circulated by the compressor to condense in the heating operation; a switching mechanism that is provided in the refrigerant circuit and is configured to switch the flow of the refrigerant in the refrigerant circuit when switching between the heating operation using the condenser and a defrost operation that defrosts the evaporator, an expansion mechanism that is provided in the refrigerant circuit and is configured to cause the refrigerant flowing between the evaporator and the condenser to expand so that the pressure of the refrigerant is reduced, and a control unit configured to control the refrigeration apparatus, characterized in that the control unit is configured to control the operating frequency of the compressor and an opening degree of the expansion mechanism during the defrost operation such that a high-pressure value of the refrigerant circuit in the defrost operation is lower than a high-pressure value of the refrigerant circuit in the heating operation, and in that the control unit is configured to control the refrigeration apparatus such that an end-of-defrost frequency decrease rate being a rate of decrease in the operating frequency of the compressor in the defrost operation is set faster than a normal frequency decrease rate being a rate of decrease in the operating frequency of the compressor in the heating operation, wherein the operating frequency of the compressor is lowered at the end-of-defrost frequency decrease rate to a calm operation frequency (Fmin), which is an operating frequency equal to or greater than a predetermined value, and the compressor is arranged and configured to maintain the calm operation frequency, without stopping, when reverting from the defrost operation to the heating operation.