Abstract: Thirteen advance lines and three check varieties viz. , Chakwal-86, Pak-81 and Rawal-87 of wheat were planted at nine locations to estimate genotype x environment interaction. Both the linear and non-linear (pooled deviation) components were highly significant, indicating the presence of both predictable and un-predictable components of "G X E" interaction. The stability parameters for the individual genotype revealed that the genotypes, 89R-35 and 90R-36 showed the regression closer to unity along with low deviation from regression and thus may be stated as stable genotypes.