Microplastics have recently emerged as major pollutants widely occurring in the atmosphere, seawater, and soils. Microplastic toxicity in plants results in economic losses from declining crop yields. Here, we review microplastic toxicity in plants with emphasis on plant growth and development, oxidative stress, hindering nutrient absorption, metal absorption, physical plant damage, toxicity mechanisms, and synergy with other stressors. We discuss consequences on metabolic pathways, gene expression, and plant–microbe interactions.