In this work, a numerical study on the natural convection heat transfer phenomenon from an inclined plate finned channel is performed for variable property fluid. Computations are performed for a range of parameters including dimensionless fin spacing (S*) = 0.3 and 0.5, dimensionless clearance (C*) = 0.10-0.50, fin height (H) of 0.03 and 0.04, and angle of inclination (theta) = 30 degrees, 45 degrees and 60 degrees. For all the values of theta, a decrease in the maximum average pressure (P*) is observed with the increase in clearance. Boussinesq fluid with constant properties predicts the heat transfer phenomenon higher by 15% than variable fluid properties, at the highest value of theta. It is also found that the induced velocity (W-in) increases nearly by 100% with the rise in angle of inclination from 30 degrees to 60 degrees. Increase in the fin conductivity (k) from 75 to 150 W/(m K) enhance the heat transfer by 14%. An initial increase in C* value from 0.1 to 0.25-0.4, a maximum of 20% enhancement in heat transfer rate is observed, however, a further increase deteriorates the heat transfer. The highest value of the Nusselt number is observed at theta = 60 degrees, which is about 40% and 60% higher than those observed at theta = 45 degrees and theta = 30 degrees, respectively.