The Balkan Peninsula is a region in Southeastern Europe, defined by the Adriatic, Black, and Mediterranean Seas. The family Tetranychidae Donnadieu, 1876 comprises 1364 species classified into six tribes and 80 genera. Among them, the most economically important and widely distributed genera are Tetranychus, Eutetranychus, Panonychus and Oligonychus. The knowledge about their diversity, host plants and habitats in Balkan countries is incomplete due to their worldwide distribution and economic importance. The present study aimed to provide a comprehensive review of spider mite diversity, habitats and host plants reported from the Balkan region and to update the existing number of species by incorporating new data obtained through recent surveys. Mites were collected from the plants during a growing season from May to October. Sampling was conducted in agricultural, forest, rural and urban habitats. All the specimens were temporarily preserved in 70% ethanol and then cleared in lactic acid (50%) for 24 – 48 hours and mounted in Hoyer’s medium. Mites were examined using a Leica DMLB II phase contrast microscope. Previous studies indicate that 74 spider mite species have been recorded on more than 130 host plants and more than 35 habitats in the Balkan Peninsula. Most available data originates from Greece and Serbia. There are 64 species from Greece, and according to the SMW (Spider Mite Web) there are 46 spider mite species from Serbia. During the field research conducted from 2021 to 2025 two additional tetranychid species were recorded from Serbia: Eotetranychus libocedri, McGregor, 1936 and Eotetranychus thujae, Reck, 1947. Data about spider mite diversity from Albania and Montenegro are as follows: four from Montenegro: Panonychus ulmi, P. citri which are officially present for decades and Tetranychus urticae, and T. turkestani which are officially recorded in past five years. Croatia officially has three spider mite species: Eotetranychus carpini, P. citri and Tetranycopsis horridus, although there are a few new species known to occur such as P. ulmi, T. urticae and T. turkestani. According to SMW in Bulgaria there are 12 spider mite species and eight species recorded from Romania. To date, there are no records of spider mite diversity for Bosnia and Herzegovina and North Macedonia. Overall, the Balkan Peninsula remains insufficiently studied in terms of tetranychid diversity, and further systematic surveys are necessary to clarify species distribution and host associations.