In this paper, free convection in an inclined stepped chamber has been studied. One wall of this enclosure is kept cold and the opposite wall equipped with constant heat source. The remaining walls are maintained adiabatic. There is one adiabatic step on the bottom wall. The aim of the present study is to forecast the effect of Raleigh number, slope of enclosure, step dimension, and heat source position, on the stream field, temperature and heat transfer rate. In this regard, two dimensional equations of mass conservation, linear momentum and energy are solved by applying finite volume method and simple algorithm. Results indicate poor effect of enclosure slope, step height, and position of heat source in small Raleigh numbers, however in large Raleigh numbers significant effects on fluid and rate of heat transfer of enclosure are observed.