Smoking does have damaging effects on the skin over a number of years. Chemicals absorbed from tobacco smoke can damage connective tissue that lies underneath the skin, which results in wrinkling. People who have smoked for a long time usually have 'old-looking skin'.
But tobacco, while deteriorating the appearance of the skin over a period of time, in itself does not seem to cause acne. So, stopping smoking could be part of a general programme of overall skin improvement.
Acne and your diet