Drought stress poses a serious threat to agricultural growth and productivity worldwide as climate change worsens. bHLH transcription factors play a significant and diverse role in plant stress response, yet the regulatory network of bHLH transcription factors in eggplant ( Solanum melongena L.) under drought stress remains unclear. Here, we cloned SmMYC2 gene from “March eggplant” leaves, which belongs to the bHLH transcription factor (TF) family and located in the nucleus. Through quantitative real-time PCR (qRT-PCR), we demonstrated that SmMYC2 expression was substantially higher in leaves, with tender leaves expressing the most and fruits expressing the least. Compared with the wild type (WT), the SmMYC2 overexpression eggplants plants ( SmMYC2-OE) showed enhanced drought resilience, lower MDA conten, higher SOD content in the leaves, but no significant difference in POD enzyme activity after drought treatment. Meanwhile, SmMYC2-OE plants exhibited a considerable increase in stem thickness and we found that the SmMYC2 gene can bind to the SmNST1 promoter to participate in the regulation of secondary cell wall (SCW) thickening. Furthermore, double molecule fluorescence (BiFC) assay and luciferase complementation (LCI) analysis showed that SmMYC2 can interacts with SmJAZ1, SmJAZ3, and SmMYB21 in vivo. Through the yeast one-hybrid (Y1H) assay and the luciferase reporter system (LUC) assay, we revealed that SmMYC2 engaged in negative feedback regulation by binding to its own promoter and inhibited its transcription in eggplant. Additionally, we found that SmMYC2 can also bind to SmMYB108 promoters and decrease its expression but act as an activator and interact with SmNST1 promoter in vivo. Together, the results of this study may reveal that SCW thickening is related to enhanced drought resistance in eggplants, and further provide insights into its regulatory network, which may greatly improve agricultural productivity.