The invention is a kind of method to make the cyclopentanone from the cyclopentanol through the catalysis rectification. We get the cyclopentanone with high purity from the material of cyclopentanol after the catalysis dehydrogenation and rectification reaction. The temperature of the dehydrogenation reaction is between 130deg.C and 140deg.C and at the normal pressure. The catalyzer of the dehydrogenation reaction is granular Raney nickel metal alloy and is composed of Al-Ni-A. The A is one of the Cr, W, Mo or Fe and the weight ratio of the components is Al:Ni:A=1:(0.8 to 0.94):(0.03 to 0.2). The cyclopentanol charge of the catalyzer is between 0.3 hr-1 and 1.5 hr-1 and. The outcome of the dehydrogenation reaction is discharged in the gas phase and can be rectified directly and the reflux ratio is controlled between 1:1 and 10:1. The selectivity of the outcome reaches 100% and the conversion of the cyclopentanol and the purity of the outcome are 98%. It is featured by the low energy consumption, high conversion of the raw material, no by-product, low production cost and green technique.