A photovoltaic power conversion apparatus, comprising: a first housing, a power component, at least one second housing, and at least one wiring terminal, wherein the first housing comprises a first housing body and a first cover plate, and the first housing body and the first cover plate are sealingly connected by using a first sealing connector to form a first accommodation cavity; the first housing body comprises a first top wall, a first bottom wall, a back plate wall, and two first side walls; and the first accommodation cavity is a sealed accommodation cavity; the power component is fixedly disposed in the first accommodation cavity; the at least one second housing comprises a second housing body and a second cover plate that is detachably connected to the second housing body, and the second housing body and the second cover plate form a second accommodation cavity; the second housing body comprises a second top wall, a second bottom wall, an installation wall, and two second side walls; and a cable inlet/outlet is disposed on the second bottom wall; and the second cover plate is configured such that the installation wall and the second cover plate are arranged on opposite sides of the second accommodation cavity; the at least one second housing is disposed outside the first accommodation cavity, and it is disposed outside a connection area of the first side wall of the first housing by using the installation wall of the second housing, so that at least a part of the installation wall is attached to or installed on the first housing; and the wiring terminal sealingly penetrates through a part of the connection area of the first side wall of the first housing and the installation wall of the second housing at the same time; a first end of the wiring terminal is located in the first accommodation cavity and is coupled to the power component disposed in the first accommodation cavity; and a second end of the wiring terminal is located in the second accommodation cavity and is configured to connect to a power cable of the photovoltaic power conversion apparatus. a first housing, a power component, at least one second housing, and at least one wiring terminal, wherein the first housing comprises a first housing body and a first cover plate, and the first housing body and the first cover plate are sealingly connected by using a first sealing connector to form a first accommodation cavity; the first housing body comprises a first top wall, a first bottom wall, a back plate wall, and two first side walls; and the first accommodation cavity is a sealed accommodation cavity; the power component is fixedly disposed in the first accommodation cavity; the at least one second housing comprises a second housing body and a second cover plate that is detachably connected to the second housing body, and the second housing body and the second cover plate form a second accommodation cavity; the second housing body comprises a second top wall, a second bottom wall, an installation wall, and two second side walls; and a cable inlet/outlet is disposed on the second bottom wall; and the second cover plate is configured such that the installation wall and the second cover plate are arranged on opposite sides of the second accommodation cavity; the at least one second housing is disposed outside the first accommodation cavity, and it is disposed outside a connection area of the first side wall of the first housing by using the installation wall of the second housing, so that at least a part of the installation wall is attached to or installed on the first housing; and the wiring terminal sealingly penetrates through a part of the connection area of the first side wall of the first housing and the installation wall of the second housing at the same time; a first end of the wiring terminal is located in the first accommodation cavity and is coupled to the power component disposed in the first accommodation cavity; and a second end of the wiring terminal is located in the second accommodation cavity and is configured to connect to a power cable of the photovoltaic power conversion apparatus.