The invention discloses a biphenyl amide compound with antitumor activity as well as a preparation method and application thereof. The structural formula of the compound is shown in the specification, wherein in the structural formula, R1 is hydrogen or halogen; R2 is alkoxy with carbon number of 1-4; the terminal of R2 is replaced by tert-amido; R2 is linked to the para-position of amide via an oxygen atom. The compound has good tumor cell inhibiting activity in vitro and can be used for preparing antitumor drugs, especially anti-hepatoma drugs and anti-breast cancer drugs. The preparation method of the biphenyl amide compound, provided by the invention, has the advantages that the raw materials are accessible, the reaction conditions are mild, the reaction process is simple to operate, and the used reagent is cheap.