In order to provide reference for milling parameters matching with asphalt milling machine,cutting load characteristics were studied on LXH1000 hydraulic asphalt milling machine.Using mathematic analysis method,motion trajectory of cutter was studied,and the model of cutting thickness and cumulative cutting thickness of rotor was built as rotor angle varying.Impact of cutting load was analyzed,and field cutting tests were conducted to validate the conclusions.The results show that cumulative cutting thickness of rotor has a periodic change with high frequency,and the period is determined by rotating speed of rotor and the number of cutters installed on it,the average is determined by rotating speed of rotor and speed of asphalt milling machine,but there is no apparent link between the periodic change and cutting load fluctuation.