Energy crisis is one of the most important problems the world is facing now a days. With the increase of cost of electrical energy operating cost of cold storage storing is increasing which forces the increased cost price of the commodities that are kept. In this situation if the maximum heat energy(Q) is absorbed by the evaporator inside the cold room through convective heat transfer process in terms of heat transfer due to convection and heat transfer due to condensation, more energy has to be wasted to maintain the evaporator space at the desired temperature range of 2 to 8 degree centigrade. In this paper we have proposed a theoretical heat transfer model of convective heat transfer in cold storage using Taguchi L9 orthogonal array. Velocity of air (V), Temperature difference (dT), Relative Humidity (RH) are the basic variable and three ranges are taken each of them in the model development. Graphical interpretations from the model justify the reality through anova and s/n ratio calculation.