Phosphorus (P) is an essential macronutrients for plant growth. Brazil depends on the annual import of large quantities of fertilizers for agricultural purposes. Domestic and agro-industrial wastewater are promising secondary P sources for nutrient recovery from struvite synthesis. In this study, domestic and agro-industrial wastewater were evaluated as anthropogenic sources of P and nitrogen (N) for struvite precipitation under optimized conditions established in previous work by the group. The syntheses were performed with phosphorus concentrations of 300 mg/L, molar ratio of 1:1:2 (Mg: P: N) and a pH 10. Characterization was conducted using X-ray diffraction (XRD) and scanning electron microscopy (SEM/EDS). Preliminary agronomic tests using soils typical of the Amazon region showed promising results. Struvite is a high-quality, slow-release fertilizer suitable for agricultural use. The use of secondary P sources in struvite synthesis is a sustainable nutrient recycling alternative for agricultural applications in Amazonian soils.