The invention relates to a method for the preparation of cyclohexanone from cyclohexane. The invention relates more particularly to a method for the production of cyclohexane whose impurity content enables cyclohexanone to be used as a raw material for the production of e-caprolactam. The inventive method consists in treating the mixture of cyclohexanol/cyclohexanone arising from oxidation of cyclohexane by oxygen in a dehydrogenation stage in order to transform cyclohexanol into cyclohexanone and the impurities present such as cyclopentenal. The inventive method makes it possible to obtain highly pure cyclohexanone which is compatible when used as a raw material in the synthesis of e-caprolactam.