The invention discloses a refining method for enhancing cleanliness of steel, which comprises the following steps: tapping molten steel obtained by converter smelting into a ladle, carrying out LF (ladle furnace) refining and casting, wherein pre-deoxidation alloying and desulfurization with high-basicity refining slag are performed in the tapping process, and a low-aluminum slag modifier is adopted to modify the ladle top slag after the tapping finishes. The LF refining process comprises the following steps: sending the ladle into the LF, adding the high-basicity refining slag, low-aluminum slag modifier and aluminum shots into the molten steel in batches while blowing argon into the molten steel in the ladle, wherein the Als content in the molten steel is controlled at 0.03-0.05 wt% in the LF refining process. In the continuous casting billet obtained by the method, the sulfur content is less than or equal to 0.003%, the inclusion indexes are respectively less than or equal to Grade 1.5, and T[O] is less than or equal to 20*10<-6>.