Channel performance parameters of Beidou shortmessage communication (BDSMC) are urgently needed. There are few analysis results of civilian channel performance, especially lack of test data for huge data. The impact of sample size on statistical results is analyzed, and the calculation methods of minimum sample size for transmission success rate and transmission delay in BDSMC are presented. A long time channel test is conducted and a great deal of test data that meets statistical requirements is obtained. The statistics results show that the transmission success rate of single packet is 95.5% and the average transmission delay is 3.8 s. Test samples obtained make up for the lack of civilian Beidou channel test data. The results can be used as a reference in the BDSMCbased system design.