The main contribution of this article is to define a certain subclass of generalized harmonic univalent rational functions. Complex-valued harmonic functions that are univalent and sense preserving in the unit disk U can be written in the form f=h+g ̅, where h and g are analytic in U. In the study of harmonic functions geometric properties of certain subclasses were discussed. Conditions of characterization involving bounds on the coefficients lead to various external properties. We further define a new subclass of harmonic rational functions and also find their coefficient characterization and certain geometric properties such as star-likeness, convexity and growth and distortion bounds for the functions of the subclass. Convolution property and extreme points of the subclass has been discussed.