Under the condition of ultrasonic wave heating,the ground oil sand from Daqing oilfeld was preprocessed with compound modifcation reagent.In order to separate oil and sand,flotation machine is used and orthogonal test is carried out to optimize the process conditions.The test results show that under the conditions of modifcation reagent concentration of 10.0 g/L,ultrasonic wave intensity of 53 kHz,power of 75 kW,temperature of 50℃ and duration of 10 min,the Daqing ground oil sand with the initial oil content of 30.80%can be transformed into dry sludge with a sharply reduced residual oil content of0.66%after being preprocessed with ultrasonic wave and separated by flotation machine.The solid particle size compositions and major components were analyzed with a laser particle size analyzer and X-ray analyzer(LS-100Q),and GC-MS as well as FITR were adopted to analyze the oil phase.The mechanism of action of intensifying separation of oil sand with the effect of ultrasonic wave was analyzed. Under the condition of ultrasonic wave heating, the ground oil sand from Daqing oilfeld was preprocessed with compound modifcation reagent. In order to separate oil and sand, flotation machine is used and orthogonal test is carried out to optimize the process conditions. The test results show that under the conditions of modifcation reagent concentration of 10.0 g / L, ultrasonic wave intensity of 53 kHz, power of 75 kW, temperature of 50 ° C and duration of 10 min, the Daqing ground oil sand with the initial oil content of 30.80% can be transformed into dry sludge with a sharply reduced residual oil content of 0.66% after being preprocessed with ultrasonic wave and separated by flotation machine. The solid particle size compositions and major components were analyzed with a laser particle size analyzer and X- ray analyzer ( LS-100Q), and GC-MS as well as FITR were analyzed to analyze the oil phase. The mechanism of action of intensifying separation of oil sand with the effect of ultrasonic wave was analyzers ed.