Viral infections can significantly alter cellular lipid metabolism by modulating key rate-limiting enzymes, including fatty acid synthase (FASN), stearoyl-CoA desaturase 1 (SCD1), and acetyl-CoA carboxylase (ACC). Our previous study revealed the pivotal role of FASN in lipid droplet (LD) synthesis and the promotion of classical swine fever virus (CSFV) replication. However, the roles of the other two key enzymes in CSFV infection remain unexplored. In this study, we screened a library of 96 lipid metabolism-targeted compounds and identified an antiviral inhibitor of SCD1, a rate-limiting enzyme in monounsaturated fatty acid synthesis, that inhibits CSFV replication. Suppressing SCD1 activity through inhibitors or small interfering RNA knockdown reduces CSFV proliferation. However, this suppression is reversed by adding SCD1 active products (oleic acid/palmitoleic acid [OA/PA]), highlighting the essential role of SCD1 in CSFV proliferation. Mechanistically, CSFV non-structural protein p7 interacts with SCD1 and recruits it to the viral replication complex (VRC) during infection. Importantly, CSFV infection activates the endoplasmic reticulum stress pathway IRE1α/XBP1, which positively regulates SCD1 expression, leading to increased production of triglyceride (TG) and LDs and subsequently enhancing CSFV replication. In summary, our study elucidates the critical role of SCD1 in the CSFV life cycle and highlights its potential as an antiviral target for developing new therapies against