We examined the response of the invasive freshwater bivalve <i>Limnoperna fortunei</i> to air exposure under different conditions of relative humidity, at 25.00 ± 0,4°C. Survival of <i>L. fortunei</i> increased with relative humidity. Specimens exposed to air without humidity control (49 to 63% relative humidity) did not survive more than 120 hours, while those held in an elevated humidity environment survived up to 168 hours. Smaller mussels reached 100% mortality before larger ones. Consequently, in industrial systems colonized by <i>L. fortunei</i>, the periodic elimination of water for less than six days will not be an effective control mechanism.Facultad de Ciencias Naturales y MuseoInstituto de Limnología "Dr. Raúl A. Ringuelet"