Generally, the moisture absorbed in the composites plasticizes the resin. And it makes the composites expansion in volume and generates the cracking at the same time, So, the fracture is often generated in the composites by those reason. Therefore, in this study, the change of mechanical properties due to the moisture-absorption for the carbon fiber reinforced composites in comparison with basalt fiber and glass fiber reinforced composites are investigated. The specimens for the carbon, basalt, and glass fiber reinforced composites manufactured with the ASTM standard. The specimens immersed in distilled water at 80°C during 100 days and the coefficient of moisture was measured in according to the Fick's law. In addition, after drying process, the humidity-absorbed specimen under 80°C for 1 day, the recovery rate was measured. As a result, the coefficient of moisture-absorption of carbon fiber reinforced composite material was the lowest at approximately 3 % because the interface coherence with the fiber and resin are the most strong. Also, after drying process, the recovery rate was 20 percent higher than the others.