GABA synthesis, signaling, and transport in plants elucidate its diverse roles in plant physiology, including stress response, growth, and modulation of physiological processes. Unlike animals, plants have distinct pathways for GABA biosynthesis. The primary enzymatic route engages glutamate decarboxylase (GAD) and the GABA shunt pathway for GABA biosynthesis. GAD activity, regulated by calcium (Ca2+) and calmodulin (CaM), performs decarboxylation of glutamate to produce GABA. The nonenzymatic alternative pathway, such as polyamine (PA) breakdown for GABA synthesis, also exists, particularly under oxidative stress. The GABA shunt pathway connects GABA metabolism to the Tricarboxylic Acid cycle (TCA) through GABA, GABA transaminase (GABA-T), and succinic semialdehyde dehydrogenase (SSADH). The GABA signaling pathways modulate various physiological processes and stress responses and operate through GABA receptors, ion currents, etc. GABA functions as a signaling molecule, modulating ion transport, stomatal dynamics, and root growth. The aluminum-activated malate transporter (ALMT) protein family serves as GABA receptors, linking GABA signaling to ion homeostasis and stress adaptation. GABA cross talk with hormones such as abscisic acid (ABA), ethylene and auxins enhances plant resilience. GABA transporters (GATs) regulate its intracellular balance and redistribution, ensuring efficient signaling under stress. By integrating biosynthesis, signaling, and transport, GABA plays a central role in plant adaptation and development, offering potential strategies for improving stress tolerance and productivity.