Preparation method of citral

The invention provides a preparation method of citral, which comprises the following steps: controlling the key component isopentenoic acid in a citral intermediate composition within the range of 10-2000ppm, and then carrying out thermal rearrangement reaction to prepare a citral product. According to the method, the selectivity of isomerization side reaction can be effectively reduced, and the yield of the final product citral is increased to 95% or above. 本发明提供了一种柠檬醛的制备方法，通过控制柠檬醛中间体组合物中关键组分异戊烯酸在10～2000ppm范围内，之后进行热重排反应，制备得到柠檬醛产品。本发明的方法可有效降低异构副反应的选择性，提升最终产品柠檬醛的收率至95％以上。