Fruit development is particular to plants and is essential to human and animal diets. As one of the crucial components of vegetable crops, fruit vegetables are even more critical. Taking Solanaceae and Cucurbitaceae family as primary examples, a series of studies have suggested the molecular and biochemical basis for regulating the fruit development process, including the localization and cloning of many quantitative trait loci (QTLs) and related genes, the identification of transcriptional and post-transcriptional regulation, and the functional analysis of plant hormones. At the beginning of this chapter, a brief overview of several stages of fruit development is presented. Furthermore, detailed accounts of various genetic controls during the fruit development process and transcription and microRNA-mediated regulation are described in detail. Subsequently, the regulation of different plant hormones in fruit development has also been discussed. Finally, better prospects are proposed for understanding the growth regulation of these critical vegetable crops.