Support connecting device

The utility model relates to a support connecting device which comprises adapter parts and connecting screws. Multiple connecting holes arranged oppositely and fixedly are formed in the adapter parts. The connecting screws are arranged in the connecting holes. Reinforcing ribs are further arranged on the adapter parts. Adjacent stand-alone solar supports are adjustably and fixedly connected with the connecting screws in the connecting holes through the adapter parts. The adapter parts are made of galvanized stainless steel. By means of the support connecting device, the whole continuous stand-alone solar supports can be fixed to form a whole, meanwhile time is saved during installation, installation efficiency is improved, meanwhile production cost is also saved, the strength of the stand-alone solar supports is further improved, whole stability is improved, stand-alone solar wind-resistant security coefficient is improved, and the actual demand for stand-alone solar installation is met.