Islamic Medicine includes several instructions, which would be helpful in advancement of Muslims if being followed. Some of these instructions are related to different health issues. Miswak or Arak tree (Salvadora persica) belongs to the Salvadoraceae family, and is a plant mentioned in Islamic texts with regard to oral and dental health. The instructions of Islamic Medicine about the tree are a major reason for widespread use of the plant in Islamic countries. In this review paper, we addressed the evidence related to the miswak tree using Quran, hadith sources, traditional Medicine books, and some modern references. In a part of the paper, we pointed to some Quran interpretations and hadiths with regard to Islamic Medicine instructions. The Arabic term in the Quran points to the Arak tree, which has several interpretations. In some hadiths, cure from some diseases and increased wealth have been mentioned as the advantages of the miswak tree. In another part of the paper, the importance of miswak tree in traditional Medicine and pharmacy, and the experience of ancient scientists about the tree are mentioned. Finally, some new findings about the medicinal properties of the miswak plant and their main components are provided. It is found that the plant is effective in tooth decay prevention. In studies carried out on people using miswak tree, it has been shown that the need for treatment of plaque and periodontal inflammation is lower in those who use the plant. Following these valuable instructions about the plant would lead to higher personal and public health level. Considering the effects of the Arak tree, including its antioxidant, antimicrobial, cytotoxic, digestive, and constipating effects, and also with regard to its socioeconomic advantages, it is suggested that using modern technology, the regular use of this plant be encouraged.