Engine oil filter

The utility model discloses an engine oil filter which comprises a shell, a filtering net arranged at the lower end of the shell, and an upper end cavity formed in the upper end of the shell. Oil outlets are formed in the side walls of a cavity body between the filtering net and the upper end cavity. The upper end cavity is internally and sequentially provided with a spring seat and a spring from top to bottom, and the spring seat and a sealing part of the spring seat commonly divide the upper end cavity into an upper independent cavity body and a lower independent cavity body in a sealing mode. The spring seat can vertically slide in a sealing mode in the upper end cavity along with stretching and contracting of the spring, the lower cavity body of the upper end cavity is communicated with the cavity through a through hole, the sealing part of the spring seat is a sealing inner ring arranged on the outer ring of the spring seat, the upper end face of the spring seat is provided with a scale pillar with the side wall engraved with scales, and an observation hole corresponding to the scales of the scale pillar is formed in the side wall of the upper end cavity. The engine oil filter is simple in structure, high in reliability, sensitive in response and low in cost.