We describe the first case of pneumatosis cystoides intestinalis in dermatomyositis (DM) of an adult. Our patient had been in remission of her DM for years when pneumatosis cystoides intestinalis occurred. Discovery of it was concomitant with that of interstitial lung disease. The overall course of pneumatosis cystoides intestinalis was benign. We discuss the mechanism of bowel and lung involvement and hypothesize that vasculitis could be the underlying process.