The anti-virus software (named as MBA) which is designed in this research fully considers characteristics of Android Smartphone. It declines to use virus code comparison technique that would cause burdens of update and storage of virus database. Instead, the MBA software adopts a remarkable technique to detect virus inherent behavior, and thus the MBA software gains high efficiency, precisely seizes virus in time and banishes virus promptly. Moreover, it has features of low power consumption and light-weight system resource usage.