A detection method and system are used for a moving target based on multiple sensors on the same platform. N mutually independent image sensors arranged on a monolithic planar array sensor compose an image sensor group, which has a layout where n image sensors are arranged equidistantly on the same line in a travelling direction of a satellite. The method includes respectively collecting image data by the multiple sensors, performing on-board pre-processing to the image data collected by each image sensor, acquiring an image from the received pre-processed image data, and performing operation to the image from different image sensors, to recognize the moving target. The system includes sequentially connected sensor groups, an image data pre-processing device and a wireless transmitting device, a wireless receiving device wirelessly connected with the wireless transmitting device, and a moving target recognition device connected with the wireless receiving device.