The invention belongs to the field of electric vehicle charging and provides a charging system for an electric vehicle parking lot. The charging system comprises a main charging pile, an auxiliary charging pile and a plurality of charging guns. The auxiliary charging pile is in electric connection with the main charging pile. The multiple charging guns are arranged on the main charging pile and the auxiliary charging pile correspondingly. According to the charging system, layout is flexible, the characteristics of elements such as a site, the vehicle number, the route and operation are combined, thus all time buckets can be efficiently combined and utilized for charging, the solutions of a lot of pressure such as the site, pile constructing and manpower can further be intensively generated, and cost is saved.