Background: Constructed wetlands (CWs) are increasingly recognized as a nature-based solution (NbS) for improving water quality and supporting circular water management in water-scarce settings. In this review, nonconventional water (NCW) refers to water sources such as greywater, municipal wastewater effluents, and agricultural drainage water that can be treated and reused. Objectives: This scoping review aimed to map CW applications for NCW treatment in arid and semi-arid regions, synthesize reported treatment performance, and evaluate reuse suitability, with a specific focus on the Middle East and North Africa (MENA) region and the Sudano-Sahel zone. Methods: Following PRISMA-ScR guidance, literature was identified from major electronic databases and institutional repositories. Eligible studies evaluated CWs treating NCW in arid/semi-arid contexts. Extracted data included CW configuration, operational conditions, pollutant removal performance, and compliance with reuse criteria. Results: Fourteen studies met the inclusion criteria. CWs consistently achieved high removal of biochemical oxygen demand over 5 days (BOD5) (85-92%), chemical oxygen demand (COD) (80-90%), and total suspended solids (TSS) (85-93%). Nutrient removal was moderate, with total nitrogen reductions of 60-75% and total phosphorus reductions of 55-65%. Fecal coliform reduction was generally 3-4 log units, frequently meeting WHO-aligned irrigation reuse thresholds. Long-term findings indicated reasonable operational stability, although clogging and salinity build-up remained recurrent constraints. Conclusions: Framing CWs within an NbS lens highlights their dual value for pollution control and climateadaptive water reuse in arid and semi-arid regions. Across MENA and Sudano-Sahel contexts, CWs show strong potential for irrigation-oriented reuse when properly designed and maintained. Future work for the study area should prioritize long-term multi-season field validation, optimization of nutrient and salinity management, and harmonized monitoring frameworks that also include emerging contaminants to strengthen safe scale-up.