The invention relates to preparation methods of 4-formoxyl biphenyl, 4-hydroxymethyl biphenyl and 4-chloromethyl biphenyl, in particular to preparation methods which adopt biphenyl as substrate, anhydrous aluminum chloride and cuprous chloride as catalysts for preparing the 4-formoxyl biphenyl, and then use the 4-formoxyl biphenyl for preparing the 4-hydroxymethyl biphenyl and the 4-chloromethyl biphenyl. The methods have technical superiorities of high recovery ratio, simple reaction steps, easy-control conditions, applicability to industrialized production, low costs of raw materials, etc.