Plant viruses are a threat to global vegetable production, as they infect commercial crops. The risk of plant viruses spreading to different locations increases as vegetables are transported through the supply chain. National authorities have established integrated pest management approaches and plant quarantine control systems to limit the spread of plant pathogens, including viruses. Despite these countermeasures, plant viruses may still spread, as they are easily transmitted through infected planting materials and vectors, such as insects. Hence, there must also be tools to rapidly diagnose plant materials for any viral infections. Combined with other preventive measures, early detection of viral pathogens will enable growers and national authorities to devise more effective disease prevention strategies. However, the rapid and accurate detection of vegetable viruses poses a great challenge. Available techniques may be time-consuming, expensive, have inadequate sensitivity, and/or not apply to bulk plant samples. The CRISPR/Cas system, most known for genome editing, has been used as a technique for identifying viral pathogens. It is a bacterial defense system that facilitates resistance to and interference with viruses. Due to its ability to recognize and degrade specific target nucleic acids, it has also been harnessed as a molecular diagnostic tool. This chapter presents recent innovations in using CRISPR/Cas in molecular diagnostics of viral infections in vegetables. Challenges to rapid viral detection are also discussed despite the recent advances in molecular diagnostics of plant viruses enabled by CRISPR/Cas.