The invention provides a grid-connected solar photovoltaic power station monitoring system which can monitor the temperature of a photovoltaic array group string, an output current voltage and direct current (DC) combiner box, a DC combiner box, a DC power distribution cabinet, an inverter, an alternating current (AC) power distribution cabinet, in-out current voltages of a boosting transformer, input current voltages of a grid-connected point, and the environment temperature, the light irradiance and the wind speed and direction of the solar photovoltaic array group string. Measured data of all the components are gathered comprehensively, essential information of a power station, test data of monitored components and environment meteorological data are displayed and stored in real time, information such as the running conditions of the monitored components and the performance ratio of the power station is calculated out, and an actual measurement operational data base of the power station is established. The components of the photovoltaic power station and the performance and the reliability of the system are estimated comprehensively, the optimization design of photovoltaic components and the system is promoted, and real and reliable data support is provided for the research and development and the improvement of photovoltaic power generating technology.