Abstract: In coping with growth-constraining and yield-reducing abiotic stress, plants have evolved complex regulatory networks that contain transcription factors. The basic leucine zipper (bZIP), a protein–protein interaction domain found in many eukaryotic transcription factors, plays a central role in the network to control the expression of the related genes. Through conserved domains, bZIP specifically recognizes cis-acting elements (e.g., G-box and ABRE) in the promoters of target genes to finely regulate the multiple post-translational modifications including phosphorylation, ubiquitination, and SUMOylation and collectively determine the protein stability, subcellular localization, and transcriptional activity. This article reviews the structure and classification of bZIP, the regulatory transcription factor networks mediated by post-translational modifications, and the biological functions of various members in response to stresses such as drought, salinity, cold, heat, and nutrient deficiency in plants. Prospective direction of research and potential applications of bZIP for crop breeding are discussed.