The aim of the study was to examine the effect of respiratory muscle strength parameters obtained from endurance athletes on aerobic capacity levels. A total of 70 endurance athletes, 23 females and 47 males, voluntarily participated with the study. Respiratory muscle strength of the athletes were measured with a digital spirometer. Max VO2 was assessed using the cardiopulmonary exercise testing system (Cosmed K5). As a result of the research; MIP and MEP values were determined to be related to PETCO2 value at maximum load in female endurance athletes. In male endurance athletes, MEP values were determined to be related to PETCO2 values at maximum load, PETO2 values at maximum load, MaxVO2 values, VO2 values at RCP, and VO2 values at VT. Additionally, in male endurance athletes, the MIP value was determined to be related to the VCO2 value at RCP and the VTidal value at maximum load. Other Max VO2 sub parameters examined were not associated with respiratory muscle strength. Research results reveal that there are relationships between maximal oxygen consumption which is the most important indicator of aerobic performance and its sub-parameters and respiratory muscles.