Peanut web blotch is a fungal disease that affects the leaves of peanuts, significantly impacting yield and quality when severe. Therefore, identifying disease-resistant germplasm is of great importance for peanut production. In this study, a genetic model analysis and QTL mapping of resistance to web blotch were conducted using an advanced RIL population of 807 lines derived from a cross between ''Huayu 44'' and ''DF12.'' The analysis showed that the resistance to peanut reticulostasis was mainly controlled by the MX1-A-AI model, which combined a pair of additive main genes and multiple genes that interacted with additive and epistasis. The heritability of these main genes was 63.44%, 60.70% and 74.64% under the three different environmental conditions, respectively. A total of five QTLs associated with web blotch resistance were identified: qDIA02.1, qDIA02.2, qDIB07, qDIB08, and qDIB09, distributed across four linkage groups, explaining 4.68%-15.91% of the phenotypic variation. Among these, qDIA02.1, qDIB07, and qDIB09 were consistently detected across the three environments, explaining 5.15%-9.43%, 7.62%-15.91%, and 5.24%-6.16% of phenotypic variation, respectively. Notably, qDIB07 was identified as a major QTL, indicating that peanut web blotch resistance is predominantly regulated by major gene effects. The results of this study not only provide a basis for the accurate localization of resistance genes to peanut web blotch but also offer a theoretical foundation for the genetic improvement of disease resistance in peanuts.