Background and aimsMitogen-activated protein kinases (MAPKs) have been reported to respond to various stimuli including heat stress. This research aimed to investigate whetherStMAPK1is implicated in the transduction of the heat stress signal to adapt heat stress as a thermos-tolerant gene.Materials and methodsPotato plants were cultivated under mild (30°C) and acute (35°C) heat stress conditions to analyze mRNA expression ofStMAPKsand physiological indicators.StMAPK1was up-regulated and down-regulated by transfection. Subcellular localization of StMAPK1 protein was observed by fluorescence microscope. The transgenic potato plants were assayed for physiological indexes, photosynthesis, cellular membrane integrity, and heat stress response gene expression.ResultsHeat stress altered the expression prolife ofStMAPKs.StMAPK1overexpression changed the physiological characteristics and phenotypes of potato plants under heat stresses.StMAPK1mediates photosynthesis and maintains membrane integrity of potato plants in response to heat stress. Stress response genes (StP5CS,StCAT,StSOD, andStPOD) in potato plants were altered byStMAPK1dysregulation. mRNA expression of heat stress genes (StHSP90,StHSP70,StHSP20, andStHSFA3) was affected byStMAPK1.ConclusionsStMAPK1overexpression increases the heat-tolerant capacity of potato plants at the morphological, physiological, molecular, and genetic levels.