Khat or qat (Catha edulis) is a plant that grows in East Africa and southern Arabia. The leaves and twigs of this small tree are chewed by several millions of people worldwide for their stimulating amphetamine-like effects. The reported prevalence of khat chewing in Europe and the USA is on the rise, especially with global migration. Long-term khat chewing has several detrimental general and oral health effects. The aim of the present study was to review the current literature regarding khat use and its association with oral and dental diseases, with particular emphasis on its link with oral keratotic white lesions and oral cancer. We searched the literature to identify all relevant articles. Studies showed that khat is associated with several oral and dental conditions, including keratotic white lesions, mucosal pigmentation, periodontal disease, tooth loss, plasma cell stomatitis, and xerostomia. There are limited data on the incidence of dental caries among khat chewers. The evidence that khat chewing is a risk factor for oral cancer is still weak, and is mainly based on anecdotal case reports and uncontrolled studies.