Monitoring data storage method and monitoring system thereof

A monitoring data storage method comprises the following steps: acquiring video information and a characteristic value of a target within an acquisition monitoring range; establishing a video streaming and transforming the acquired video information into a video file for processing device storage; storing the video file in a first folder in a hard disk of a processing device; detecting if the characteristic value of the target is more than a threshold value within the acquisition and monitoring range, if so, extracting a picture file from the established video streaming and storing the picturefile into a second folder in the hard disk of the processing device; and if not, proceeding the detection steps; and sending the stored picture file to a network hard disk according to a designated email address. In the method, when the target fitting for an alarming characteristic enters the monitoring range of a sensor, a monitor sends a signal to a processor, and the processing device extractsthe picture file from the video streaming and then sends the picture file to the designated mail box of a user; and even though a storage unit of the processing device is faulty or damaged, the usercan also obtain the information within the monitoring range, thus realizing higher safety. In addition, the invention further provides a monitoring system for realizing the monitoring data storage method.