The present invention relates to an active sound design (ASD) system for adjusting and controlling a volume of a virtual engine sound/synthetic engine sound according to a vehicle speed, and to an adaptive sound control system and method of an ASD system capable of keeping driving sound quality constant by actively controlling the ASD sound in consideration of the in-vehicle noise level since an in-vehicle noise (background noise) level varies according to different conditions (road surface noise, wind noise, etc.) even with the same vehicle speed.