Objectives. To determine the frequency, clinical features, and factors associated with M. ozzardi infection in volunteers of a malaria screening campaign in the district of Alto Nanay in the Amazon jungle of Peru. Materials and methods. A descriptive, analytical and cross-sectional study was performed. The participants were interviewed and examined by a physician and the data were recorded in a medical record. The diagnosis of M. ozzardi infection was performed using the method of thick blood smear and film. Results.The frequency of mansonelosis in this population was 47.8% (95% CI: 39.1 to 56.6). Through bivariate analysis we found that the report of decreased visual acuity or blurred vision and presence of subcutaneous tumors were the signs and symptoms statistically associated with the infection of microfilariae (p<0.05). Logistic regression found statistical association for residency in localities of the Pintuyacu or Alto Nanay rivers, employment in places far from the town center, the presence of subcutaneous tumors and skin thickening (p<0.05). Conclusions. There was a high number of mansonelosis by M. ozzardi in the district of Alto Nanay which was significantly related to working outside the town center, residing in the area of the Pintuyacu River, and skin lesions.