Based on the density functional theory and the quasi-harmonic Debye model, the structural and thermodynamic properties of I-4m2-BCN have been studied in this paper. Some structural parameters are presented in this work. All of these results are in excellent agreement with the other available results. The anisotropy of elastic properties are also studied systematically in this paper. Finally, the thermodynamic properties of I-4m2-BCN are also researched through the quasi-harmonic Debye model. The relations among the thermal expansion α, the Debye temperature ΘD, the heat capacity CV and CP , the Grüneisen parameter γ, entropy S, and the Gibbs free energy G with pressure P and temperature T are studied systematically.