The invention discloses an air filter, an air filtering method and a suitable air purifying device. The air filter is used in the air purifying device. The air purifying device comprises an air inlet pipe and a draught fan located at an air outlet of the air inlet pipe. The air filter comprises multiple rows of charge discharging pointed ends arranged in the air inlet pipe and a filtering screen set with positive electricity and negative electricity, wherein the charge discharging pointed ends comprise one row of positive charge discharging pointed ends and one row of negative charge discharging pointed ends, each row of charge discharging pointed ends comprise at least one discharging pointed end, and the filtering screen set is arranged between the two rows of charge discharging pointed ends and the draught fan. By means of the air filter, the air filtering method and the suitable air purifying device, air can be more effectively purified.