The utility model relates to a photovoltaic wiring box with an improved box body structure. The photovoltaic wiring box with the improved box body structure includes a box body and an electric conducting assembly arranged in the box body. The box body includes a leading-in zone arranged on the upper part of the box body and used for connecting with bus bars, and a working zone arranged on the lower part. The working zone includes a box cover arranged integrally with the box body and a bottom board buckled below the box cover. The working zone is also provided with a glue filling zone. A distance is kept between a box wall of the working zone and a box wall of the glue filling zone, so that a heat dissipation zone is formed. The electric conducting assembly is arranged in the glue filling zone. The heat dissipation zone is provided with heat dissipation holes. According to the utility model, through improvement of box body structure, production cost of the photovoltaic wiring box with the improved box body structure is reduced and heat dissipation performance of the box body is guaranteed at the same time.