Abstract: In order to investigate the effect of collector, foaming agent and ultrasound frequency on enrichment rate of vitrinite. Single factor experiments and response surface experiments were carried out with a self-designed ultrasound flotation device, the surface morphology and pyrolysis characteristics of flotation concentrate were explored by SEM, FTIR and TGA analysis. Research results shown that when the collector, foaming agent and ultrasonic frequency was 0.9g/L, 0.11g/L and 100KHz, the enrichment rate of vitrinite reached a maximum of 76.98%. The response surface experiments shown that the enrichment rate of vitrinite could reached a maximum of 79.27%. Ultrasound treatment reduced the surface minerals of coal, and the TG analysis shown that ultrasound treatment decreased the weight loss and the rate of weight loss of vitrinite, while had no significant impact on inertinite. FTIR shown that oxygen-containing functional groups of vitrinite was higher than that of inertinite, while aromatic hydrocarbon of was less than that of inertinete.