The purpose of this research was to carry out the physicochemical characterization of a wild fruit of cactaceae (Haageocereus pseudomelanostele). For this, fruits free of lesions and contaminants were selected, from the Ancash region (Peru). The fruits had the following characteristics: carbohydrates 7.22 g / 100g; ash 0.43 g / 100g; dietary fiber 2.26 g / 100g; Brix 5 degrees; fat 0.12 g / 100g; humidity 91.58 g / 100g; pH 3.3; 0.65 g / 100g protein and a vitamin C content of 66.73 mg / 100g of fresh pulp. After characterization, the fruits were dehydrated, using four methods: convection dried, lyophilization, lyophilization with preliminary osmotic dehydration, lyophilization with preliminary osmotic dehydration and maltodextrin. Subsequently, the concentration of vitamin C in the four dehydrated samples was determined. The results obtained were statistically evaluated, using an analysis of variance (ANOVA) where it showed a statistically significant difference between treatments (p <0.05). The lyophilization treatment being the one that conserves the most vitamin C content in the wild fruit of cactaceae (Haageocereus pseudomelanostele).