Abstract: Following an introduction to the structural design and working principle of the pressure filter with the HBF-S120 version used at Majiliang Coal Preparation Plant as an example, the paper goes to analyze the causes behind the common faults of the filter in operation, such as low air pressure in pressure chamber, scraper conveyor issuing failure alarms, incapability of the switches of both upper and lower sluice gates to move to correct positions, timeout of air intake and blowing operations due to breakdown of upper and lower sealing rings, and timeout of air charging and blowing operations of cake discharge chamber. The use of the remedial measures proposed has led to much enhanced stability and utilization rate of the pressure filter.