Coal slime is a kind of solid waste and inferior fuel, which is urgently needed to utilize. In this paper, a high-temperature thermal treatment of coal slime in a circulating fluidized bed（CFB） was attempted to achieve resource utilization. In the experiment, the combustion characteristics of dried coal slime during high-temperature thermal treatment were investigated in a 0.5 MW pilot-scale CFB. The stable fluidized combustion of dried coal slime was realized. When the excess air ratio was closer to 1.0, the furnace temperatures would be uniform. The ignition method of dried coal slime was changed correspondingly while the feeding position changed. However, feeding coal slime to the loop seal was instrumental in decreasing NOx emissions. Moreover, the NOx emissions were tried to further control by the post-combustion technology. Post-combustion technology could significantly reduce NOx emissions below 50 mg·Nm-3 while ensuring combustion efficiency. Besides, it was found that there was an optimum excess air ratio in CFB of about 0.9 resulting in minimum NOx emissions of coal slime. The experiment results could well guide the industrial-scale high temperature thermal treatment of coal slime.