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The use of models affords an understanding of hydrological processes under different environmental conditions, and aids action planning in the face of changes in land use, soil, and climate. Arid and semi-arid regions are the most vulnerable to climate change. To this effect, the SWAT model has been used in different locations around the world and in various applications. This work analysed recent studies published between 2009 and 2022, to understand the following: (1) how the SWAT model has been applied in arid and semi-arid regions of the world, (2) the criteria used in applying the model, and (3) what alternatives can be used to overcome the limitation of input data and improve SWAT performance in dry environments? A systematic search was conducted based on scientific articles. A total of 234 articles were identified where SWAT was used drylands. The largest and the smallest applications were implemented in Asia and Oceania respectively, in such segments as agriculture, water governance, environmental conservation, hydrological processes, and extreme events. The number of years of data used for calibration and validation was generally low (<20 years), with a median of 9 for calibration and 6 years for validation. The NSE (92%) was the most applied in analysing modelling efficiency, followed by the R2 (78%) and PBIAS (51%). The lack of observational data in the drylands is still a major challenge for studies que involving hydrologic modelling, and to improve the hydrological responses, researchers use strategies such as the use of data measured in the field, remote sensing, and even application of other models with or inside the SWAT. [ABSTRACT FROM AUTHOR]