1. A pedestrian detecting system, comprising: a radar detecting and obtaining spatial information of a target object; a camera capturing an image of the target object and recognizing the image, thereby obtaining image feature information of the target object; and a computer electrically connected to the radar and the camera, wherein the computer receives the spatial information and the image feature information and performs a scoring scheme to detect and determine if the target object is a pedestrian; wherein an appearance confidence is obtained through data transformation of the image feature information, and a spatial confidence is obtained through data transformation of the spatial information, and the scoring scheme performs weighted scoring on the spatial confidence and the appearance confidence to obtain a composite scoring value to determine if the target object is the pedestrian; wherein the appearance confidence is calculated using the following equations: P appearance ⁡ ( B ) = 1 1 + e - α × tan - 1 ⁡ ( s ⁡ ( X B ) × π 2 ) ; where s(X B ) represents a scoring value corresponding to a feature vector X in an image boundary region B of the target object; the spatial confidence is calculated using the following equation: 
 P spatial ( B )= P associate ( c I ,c R *); where P associate is a probability corresponding to each coupled position (C I , C R ), and C R * is a best matching that has a highest probability to each position C I ; and the scoring scheme is calculated using the following equation: 
 P fusion ( B )=(1− w r )× P appearance ( B )+ w r ×P spatial ( B ); where Wr is a weighted ratio.