In the classical inventory model the holding cost was assumed to be constant. However, in reality holding cost may not always be constant. The holding cost may be time dependent. In this paper, a production inventory model with deteriorating items with constant, linear and quadratic holding cost is considered and also a comparative study is carried out between constant holding cost and time dependent (linear and quadratic) holding costs. Three models are developed. In three models, the optimum time and total cost are derived when the holding cost is: 1) constant; 2) linear; 3) quadratic. A mathematical model is developed for each model and the optimal production lot size which minimises the total cost is derived. The optimal solution is derived and an illustrative example is provided. The validation of result in this model was coded in Microsoft Visual Basic 6.0.