<p>The plant hormone abscisic acid (ABA) plays an important role in regulating plant growth and development. In order to explore the regulatory role of ABA in tomato pollen maturation, the expression of <i>SlNCED1</i>, which encodes 9-cis-epoxycarotenoid dioxygenase (NCED), a key enzyme in ABA biosynthesis, was up-regulated by gene over-expression (OE) technique. Four independent transgenic lines were obtained by transforming tomatoes using the leaf disk method infected with <i>Agrobacterium tumefaciens</i> LBA4404. Two independent transgenic lines, <i>SlNCED1</i>-OE2 and <i>SlNCED1</i>-OE9, were extensively subjected to physiological, biochemical, and molecular testing. The results showed that the ABA content in the anthers of transgenic lines <i>SlNCED1</i>-OE2 and <i>SlNCED1</i>-OE9 was up-regulated by 2.19 times and 1.84 times compared to the wild type (WT), respectively. Compared with the control, the pollen vitality of the transgenic lines significantly decreased to 14.34% and 30.5%, respectively. Microscopic observation revealed significant abnormalities in the pollen maturation process of transgenic lines, with delayed degradation of the tapetum and even varying degrees of microspore adhesion. Moreover, the expression of tapetum transcription factor genes <i>SlDYT1</i>, <i>SlTDF2</i>, <i>SlAMS</i>, <i>SlbHLH</i>, <i>SlMYB80</i> and <i>SlCysp1</i> were significantly up-regulated, while the expression of <i>SlAsp1</i> and <i>SlSSC</i> was significantly down-regulated in transgenic lines. In conclusion, ABA is involved in the degradation of tapetum and thus affects pollen maturation by regulating the expression of tapetum transcription factor genes in tomato.</p>