This study was carried out to check the structural safety of greenhouses for the four typical types(A-1,A-2,B-1,B-2) based on structural analysis by comparing with both design wind velocity and design snow depth of 15 years recurrence interval. When analyzing structural behaviors under unit snow load and unit wind load, the deflections as well as such section forces as axial forces, shearing forces, and bending moments, shows similar trends regardless of the various greenhouse dimensions. Generally the maximum section forces were commonly found on the sides of windward; maximum axial forces and maximum shear forces were commonly found on each supporter; maximum bending moments were found near the eaves height. And when comparing the estimated potential wind and snow loads with those loads of 15 years recurrence interval, it was found that such modifications as increasing section modulus or narrowing pipe intervals of rafter are required against wind damage. The safe ranges of snow depth and wind velocity per the individual rafter pipe in the aspect of maximum tensile forces and maximum vertical compressions were found to be 11.9~17.4kg and 15.3~29.2kg respectively.