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Objective Metabolic adaptation to cold stress plays an important role in the growth, survival and yield of crops. Gamma aminobutyric acid (GABA) as an osmolyte may take part in counteracting the oxidative stress induced by cold stress in chickpea.   Material and methods In this experiment, content of Putrescine (Put),GABA, Hydrogen Peroxide (H2O2), activity of Diamine Oxidase (DAO) andrelative expression ofGlutamate Gecarboxylase1 (GAD1)gene in cold-tolerant (Sel96th11439) and cold-sensitive (ILC533) chickpea (Cicer arietinum L.) genotypes under cold stress (4°C)as a factorial experiment in a Completely Randomized Designwere studied.   Results In tolerant genotype H2O2 content after a significant increase on the first day of cold stress decreased significantly on the sixth day of cold stress compared to control conditions (up to 4.7%) while its accumulation was observed in sensitive genotype (up to 50%). These results indicated a relative acclimation to cold stress in tolerant genotype. Under cold stress, GABA and Put contents in tolerant genotype was higher compared to sensitive genotype (up to 14% and 35%, respectively). Under cold stress, in tolerant genotype increasing GABA content was accompanied with an increase in DAO activity and relative expression of GAD1 gene as biosynthetic pathways of this metabolite (up to 3- and 17-fold, respectively). The maximum activity of these two pathways was observed in tolerant genotype on the sixth day of cold stress.               Conclusions Under cold stress, the accumulation of GABA in tolerant genotype led to reduced cell damage (H2O2 results) and improved cold tolerance. These indices were useful in assessment of chickpea genotypes under cold stress and breeding programs.