Caffeine dependence is the condition of having a substance dependence on caffeine, a commonplace central nervous system stimulant drug which occurs naturally in coffee, tea, yerba mate, cocoa, and other plants. Caffeine is also one of the most common additives in many consumer products, including pills and beverages such as caffeinated alcoholic beverages, energy drinks, colas. In fact, studies have found that 89 percent of adults in the U.S consume on average 200 mg of caffeine daily. Cultural influence is a large factor in deciding how and what way caffeine is used. For example, in African, Asian and Pacific countries, tea is the popular form of caffeine, whilst in Europe and North America, coffee is the mainstream choice.

Caffeine's mechanism of action is somewhat different from that of cocaine and the substituted amphetamines; caffeine blocks adenosine receptors A₁ and A_2A. Adenosine is a by-product of cellular activity, and stimulation of adenosine receptors produces feelings of tiredness and the need to sleep. Caffeine's ability to block these receptors means the levels of the body's natural stimulants, dopamine and norepinephrine, continue at higher levels.

The Diagnostic and Statistical Manual of Mental Disorders describes four caffeine-related disorders including intoxication, withdrawal, anxiety, and sleep.