The 1:1 cocrystal of 2-amino-3-bromopyridine (2A3BP) with 4-methylbenzoic acid (4MBA) has been prepared by slow evaporation method in methanol, which was crystallized in monoclinic P2(1)/c space group having two molecules in the asymmetric unit. The cocrystal has been characterized by single crystal X-ray analysis, FTIR, H-1 NMR, C-13 NMR, and Powder XRD. Theoretical investigations have been calculated by HF and density function (B3LYP) method with the 6-311+G(d,p) basis set. The vibrational frequencies together with the H-1 NMR and C-13 NMR chemical shifts have been calculated on the fully optimized geometry of 1. Theoretical calculations of bond parameters, harmonic vibration frequencies, and isotropic chemical shifts are in good agreement with the experimental results. Solvent-free formation of these cocrystal was confirmed by powder X-ray diffraction analysis. The crystal structure was stabilized by N-pyridine-H center dot center dot center dot O = C, C = O-H center dot center dot center dot N-pyridine and C-H center dot center dot center dot Br hydrogen bonding interactions.