The bulk seed of eight pigeonpea lines was graded into large (L), medium (M) and small (S) by using sieves (10/64" x 3/64" and 9164" x 3/64"). The ungraded bulk was used as a control (C). These graded seeds were evaluated for stability of performance. Genotype x environment interaction was significant for days to maturity and primary branches per plant. ijone of the variety and its seed grade was found stable for yield over environments. However, ICPL 161 (L) for maturity, Pant A8505 (M), Pant A3 (C) for primary branches showed average stab.iJitY and wider adaptability. Large seeds and control lot accounted high mean performance than s~ll seed grade in ICPL 161, Pant A 104, Pant A 8505, UPAS 120, Type 21 and Pant A 8505.