Inflow performance relationships (IPR) have long been recognized as one of the most important diagnostic tools for predicting hydrocarbon production performance. Current IPR models associated with naturally fractured reservoirs (NFR) are only applicable to fully fractured NFR models. No previous research has investigated the IPR of partially naturally fractured reservoirs (PNFR). This work aims to develop an IPR model for horizontal wells producing from PNFRs under solution-gas drive (SGD). A 3D black oil simulator is utilized to generate the required IPR data. A total of 236 IPR plots and 26 future IPR plots are generated throughout six major cases varying in fracture intensity (FI), dimensionless well length (LD ), matrix permeability (km ), and fracture porosity (ϕf ). Percolation theory validated the existence of a critical FI threshold at which complex IPR behaviors manifest. Sensitivity analysis reveals that IPR shape becomes more complex as LD reduces. ϕf has negligible effects on IPR and future IPR behaviors. A logarithmic cycle proportionality governs the relationship between km and absolute open flow potential (qo,AOF ) in future IPR curves. A generalized IPR model applicable to horizontal wells producing from SGD PNFRs is developed through the non-linear regression of IPR candidates. The model is validated against field data and complex IPR behaviors.