The invention discloses a waste oil classifying recovering and purifying system. The waste oil classifying recovering and purifying system comprises a plurality of oil collecting cylinders, waste oil classifying mechanisms connected with the multiple oil collecting cylinders in a one-to-one correspondence mode, a first transitional tank and a second transitional tank connected with first oil outlets and second oil outlets of the multiple waste oil classifying mechanisms, a first liquid level sensor installed in the first transitional tank, a second liquid level sensor installed in the second transitional tank, a first oil storing tank connected with the fist transitional tank, a second oil storing tank connected with the second transitional tank, a diesel oil purifying mechanism connected with the first oil storing tank and a gasoline purifying mechanism connected with the second oil storing tank. According to the waste oil classifying recovering and purifying system, on one hand, diesel oil and gasoline are classified through the waste oil classifying mechanisms and conveyed to the first transitional tank and the second transitional tank correspondingly, so that subsequent purifying treatment on the diesel oil and the gasoline is facilitated; and on the other hand, detection is conducted on the liquid levels of the first transitional tank and the second transitional tank, so that quantitative conveying of the diesel oil and the gasoline is facilitated, and it is beneficial to saving conveying energy.