An experiment was conducted at Agriculture Research Station, Kalaburagi, Karnataka, India during kharif, 2015-16 to understand the effect of differential population of leafhoppers, on growth and yield parameters of pigeonpea under field conditions with seven level of population load. Maximum of 26.16 hoppers/3 leaves were found at 12 pairs release plot which was at par with 10 pairs (22.21) and 8 pairs (24.96) released which were statistically significant. The average hopper count @ 4 and 6 pairs released plots were 13.14 and 16.15 per 3 leaves respectively and were at par among themselves and significantly higher than 2 pairs release and lower than 8 pairs release plots. This was a clear indication that the differential population of leafhopper had impact in reduction of growth and yield parameters with. Reduction in yield to the tune of 3. 12, 5.29, 10.05, 17.99, 24.63 and 31.91 % at 2, 4, 6, 8, 10 and 12 pairs released plots, respectively. From the present investigation it was clear that the 5.59 to 5.77 leafhoppers aggregated in top leaf at 90 to 120 days aged crop of medium duration variety will cause 10 per cent reduction in yield.