The invention relates to a bus passenger flow statistics method and system. The method comprises the steps of obtaining a video image in a bus, and extracting each frame of a foreground image in the video image; when a bus door is in a closed state, obtaining an eigenvalue of a door opening detection area in each frame of the foreground image; judging whether the eigenvalue of the door opening detection area is larger than a first set threshold value or not; obtaining an eigenvalue of a passenger detection area in each frame of the foreground image and a time point corresponding to the eigenvalue; obtaining an obtaining of a door closing detection area in each frame of the foreground image; judging whether the eigenvalue of the door closing detection area is larger than a second set threshold value or not; and according to the obtained eigenvalue of the passenger detection area in each frame of the video image and the time point corresponding to the eigenvalue, obtaining the number ofpassengers getting on the bus during current door opening and closing. According to the bus passenger flow statistics method and system, the training of a large sample amount does not need to be performed; the calculation amount is reduced; the statistical efficiency is improved; the accuracy of statistics is improved; the requirement on hardware equipment is low; and the cost is reduced.