The invention relates to the technical field of video analysis and discloses a video quality diagnosing method comprising the steps as follows: step 101,video data coming from a remote camera to be diagnosed are obtained by a transmission server; and step 102, indexes of the video data are detected in a preset time range, and a diagnosis result is provided, wherein the step 101 and the step 102 are conducted in an asynchronous way, the video data are detected after a certain quantity of video data is cached, and the video quality is diagnosed according to the detection result. The effective video quality diagnosing method is realized by the designed methods on detecting the indexes of image definition, video loss rate, picture partial chromaticity, picture gain imbalances degrees, contrast, picture upheaval, screen freezes degrees, screen wobble degrees, stable stripe interference degrees, horizontal grain superposition degrees and noise degrees of the video data.