In the present study, pot experiments were carried out to observe the effects of simulated acid rain (pH 5.5, 5.0 and 4.5) exposures on papaya and castor plants. All levels of pH affected adversely to all growth parameters (length, fresh and dry weight of root and shoot) of both plants. The yellowing, injuries and necrotic symptoms were observed on papaya. All plant growth parameters were significantly suppressed by all the pH levels. The reductions in parameters were concentration dependent. Highest reductions in all plant growth parameters were observed in 4.5 pH treatment. The papaya was found more susceptible than castor.