It does:
Increased muscle mass -> Higher basal metabolic rate -> More calories burnt per-day.
Calories burnt during the actual workout.
But you'd obviously need a decent workout plan to atleast make your regime worthwhile (decent weights, consistency, good intensity, sound exercise plans etc.). Secondly a mistake people often make is eating more. If you do a hard workout but eat a load more shit, then needless to say it's not gonna help your weight loss.
But the main key here is HELP. It won't do you shit if you're still eating like a sumo and never do any cardiovascular activities.