Abstract: According to the poor water proofing shortage of partial upgraded lignite briquette, the emulsified silicon oil was prepared to be the water proofing agent of the briquette.During the preparation process of the silicon oil emulsion, the best hydrophilic lipophilic balance value would be 10.5, the best quality ratio of the silicon oil and the emulsifier would be 4 : 1 and the best emulsification method would be the phase inversion emulsification method.The experiment results showed that the em ulsified silicon oil as the water proofing agent could highly improve and upgrade the water resistance of the lignite briquette and three silicon oils with different quality fr actions (5%，10% and 30%) could make the briquettes previously with no water resistance to have an average 60 minutes water absorption rate reduced to 6.98%，5.5 1% and 1.98% individually.