Soybean rust (SBR) is a damaging disease that has threatened soybean production worldwide. In Brazil, the world’s top soybean exporting country, SBR-resistant cultivars have been developed to prevent severe soybean production losses. To evaluate SBR effects on soybean production in Brazil and on the global soybean market, we developed soybean supply and demand models for Brazil, the U.S., Argentina, China, the EU-28, and the rest of the world based on functions that include yield, area, exports, imports, stock changes, demands, and price linkages. Three scenarios were set: no production loss caused by SBR, severe production loss caused by ineffective fungicides, and the adoption of SBR-resistant cultivars. To evaluate the effects of SBR and SBR-resistant cultivars on soybean production and the global soybean market, our simulation results suggest that the world price of soybeans would increase due to severely damaged soybean production. The adoption of resistant cultivars can alleviate losses in soybean production and reduce costs for fungicide application. Therefore, adopting SBR-resistant cultivars in soybean production is necessary to maintain a stable global supply of soybeans.