The invention discloses an intensified distillation method for crude oil or heavy crude oil, which comprises the following steps: 1, carrying out pretreatment on crude oil or heavy crude oil by using biomass oil: uniformly mixing the biomass-oil and the crude oil or heavy crude oil at normal temperature, wherein the addition amount of the biomass-oil accounts for 0.5-10% of the volume of the crude oil; 2, carrying out secondary pretreatment: adding insulin into the step 1; placing the obtained mixture into a constant-temperature water bath environment to carry out constant-temperature heating for 2-36 hours at a heating temperature of 36-39 DEG C; and 3, carrying out atmospheric distillation on the mixture pretreated in the steps 1 and 2. The method disclosed by the invention is mild in atmospheric distillation reaction conditions and environmental friendly, and the gas-liquid yield is increased; the yield of crystal, clear and light yellow light components is significant, so that the transition temperature of color change can be increased, and the occurring temperature of stimulating odor can be delayed; and the method is simple in process, and convenient and easy to operate.