In order to facilitate the application of bio-based resins in more demanding advanced sectors as electrical and aeronautical industry, a systematic study was carried out to characterize the effect of epoxidized soybean oil (ESO), one of the most commonly used bio-based resins, on curing and rheological behavior, glass transition temperature, mechanical and thermal properties in various epoxy resin systems. Besides the conventional, widely investigated aromatic diglycidylether of bisphenol-A (DGEBA) resin, a glycerol- and a pentaerythritol-based aliphatic resin was chosen as base resin, whose synthesis is feasible from renewable materials as well, in the end leading to full replacement of mineral oil based resins by renewable sourced ones. In the hybrid resin system the ESO content was systematically increased from 0 to 100 mass%. The results indicate that in the case of the DGEBA containing hybrid systems the overall performance deteriorates with increasing ESO-content, while in the case of the aliphatic resins the glass transition temperature increases.