Since 2017, Pestalotiopsis leaf fall disease affecting para rubber trees has spread across Southeast Asia and South Asia. This novel disease represents a new risk to the livelihoods of rubber smallholders. The present study aims to investigate the impact of Pestalotiopsis leaf fall disease on the livelihoods of rubber smallholders in Indonesia. We adopt the sustainable livelihood framework for analyzing data. We first identified the context in which Indonesian rubber smallholders are situated drawing on secondary sources. Second, to understand smallholders’ livelihood situations, we conducted a household survey in Banyuasin and Muara Enim Regencies of South Sumatra Province. Vulnerability of Indonesian rubber smallholders has been increasing particularly since the 2010s, due to low rubber prices, diseases, and declining government support. Due to Pestalotiopsis leaf fall disease, latex production had decreased on average by 47.7% compared to normal conditions. Few measures had been attempted by smallholders against leaf fall disease. Whereas 60.2% of the households had income sources other than rubber, 38.8% were dependent on rubber income. Households with greater income, often owing to sources other than rubber, were more proactive in taking action to address a given situation. Our findings confirm that Pestalotiopsis leaf fall disease has significantly increased the vulnerability of rubber smallholders' livelihoods. Although rubber smallholders are not monolithic, overall, enduring the impact was the most common response among rubber smallholders. Households heavily reliant on rubber may face greater vulnerability if issues like leaf fall disease and low rubber prices persist. For future implementation of control and prevention measures currently under development, it is necessary to design methods that do not leave ordinary households behind. Additionally, some government support would be essential. © 2025 Malque Publishing. All rights reserved.