Double diffusive convection has wide application background in industry. This article numerically studies the flow characteristics of double diffusive convection phenomena around a heated cylinder in an enclosure. The heated cylinder is located at the center of the enclosure with high temperature and concentration. Inlet flow with low temperature and concentration is located at the lower-left wall of the enclosure and exited at the upper-right wall. Other walls are assumed to be adiabatic. The influences of Lewis number Le, buoyancy ratio Br and Richardson number Ri to the double diffusive convection are presented with constant Prandtl number Pr=0.7 in this article. Streamlines, isotherms, isoconcentrations and the local and average Nusselt number Nu and Sherwood number Sh are reported to inspect the flow characteristics in an enclosure.