A moving handrail monitoring system includes a sensor configured to sense at least part of a moving handrail of the passenger conveying device to acquire a data frame; a processing device configured to analyze and process the data frame to monitor whether a tension degree of the moving handrail is in a normal state, wherein the processing device is configured to include: a target object recognition module configured to recognize, based on a sensed movement and/or position and/or color and/or shape, a moving handrail portion that serves as a target object from the data frame; an object feature extraction module configured to extract a tension degree feature of the moving handrail portion; and a judgment module configured to compare the extracted tension degree feature with a system preset interval, and judge whether a current tension degree of the moving handrail is normal.