Adverse effect of caffeine consumption has been well documented in animals and in human beings. However, here we studied the influence of caffeine exposure on seedling growth of Arabidopsis and tobacco plants. Retardation in the seedling growth of these plants was observed when grown on MS medium plates containing 1 mM caffeine and their growth retarded further upon increasing the concentration of caffeine to 5 mM. Retardation in seedling size including both root and shoot size, yellowing and decrease in chlorophyll content of seedlings upon caffeine treatment indicated that caffeine exposure induced early senescence in plants. Therefore, the influence of caffeine exposure on transcript expression and activity of Rubisco in tobacco and Arabidopsis seedlings was monitored. Caffeine exposure has been found to decrease the expression and activity of Rubisco in both the plants. Hence, this study documents that caffeine exposure retarded seedling growth and one reason for this could be its negative effect on Rubisco.