Cigarette smoking is associated with various diseases in humans. Osteoporosis is one of those diseases which have not been given much attention in the past but is highly important to health issues of mankind. Furthermore the association and the pathogenic mechanisms between them are not exactly understood. In this review we shall discuss the possible mechanisms underlying this association which include hormonal changes, systemic inflammation and production of free radicals and oxidative stress. Apart from these mechanistic studies, future direction should be focused on determining the active ingredients in cigarette smoke and their detrimental actions on osteoporosis and also studying the reversal effects of smoking cessation on bone metabolism and structure. All information is useful in devising therapeutic strategies for osteoporosis and promoting cigarette smoking cessation program in our society.