Thuja is one of Coniferous trees (family Cupressaceae). It comprises five species: Thuja occidentalis, Thuja koraiensis, Thuja plicata, Thuja standishii and Thuja sutchuenensis. This review aimed at gathering the botany, traditional uses, biological activities and phytoconstituents of Thuja species from 1984 until 2020, as they are considered generous sources of numerous phytoconstituents that may be used as scaffolds for new drugs with diverse pharmacological activities.  Online bibliographies were searched using popular search engines, such as Google Scholar, PubMed, Springer, and Web of Science, in order to cover the botany, folk uses, biological activities and phytochemistry of Thuja plants. The review revealed that Thuja plants have diverse biological effects and economic and folk uses. Moreover, the review showed the different phytoconstituents classes in Thuja plants. It can be concluded that Thuja plants are good candidates for intensive research to prove their biological activities by in vivo and clinical trials in order to get evidence-based drugs and discover new drugs for the treatment of several ailments.