Chronic social isolation (CSIS) generates two stress-related phenotypes, resilience and susceptibility. Although brain energy metabolism is important in regulating social behaviors, the molecular mechanisms underlying CSIS resilience remain unclear. To identify protein changes and altered biochemical pathways and processes for resilience to CSIS, prefrontal cortical cytosolic proteomic profiling was performed comparing CSIS-resilient with CSIS-susceptible and control rats. Potential predictive proteins discriminating between the CSIS-resilient and CSIS-susceptible groups were identified by support vector machine-based sequential feature selection and random forest-based feature importance scores. Predominantly decreased levels of glycolytic enzymes, G protein-coupled receptor proteins, Ras subfamily of GTPase proteins, and antioxidant proteins were found in CSIS-resilient vs. CSIS-susceptible groups. Altered levels of Gapdh and proteins involved in microtubule and cytoskeletal organization, and calcium-binding proteins were identified between the two phenotypes. These dynamic changes were accompanied by increased levels of proteins involved in GABA synthesis, the proteasome system, nitrogen metabolism, and chaperone-mediated protein folding. The overall ratio of significantly up- and down-regulated cytosolic proteins suggests adaptive cellular alterations as part of the stress-coping process specific for the CSIS-resilient phenotype.