This study investigates the dose-response relationship between acid precipitation and malondialdehyde (MDA) accumulation in plants, utilizing sophisticated curve-fitting or linear-fitting techniques to pinpoint toxicity thresholds arising from simulated acid rain (SAR) stress. Four distinct types of dose-response relationship patterns emerged: promotion, non-affection, low promotion-high suppression, and full suppression. The research meticulously examined the dose-response relationship of the inhibition rate of MDA content in plant leaves after 50 days of exposure to SAR across 18 plant species, with pH levels of 5.6 (control), 4.0, 3.0, and 2.0. By applying precise dose-response relationship fitting, the EC10 value—reflecting the acid rain pH that elicits a 10% increase in MDA levels—was calculated, unveiling critical toxicity thresholds. The results revealed striking variations in species-specific MDA responses, offering vital insights into the ecological impact of acid rain and establishing key toxicity benchmarks for future studies.