Zeolites are a class of microporous, crystalline materials that have many applications as adsorbents, membranes, sensors, and catalysts. For use as a catalyst, zeolites can be synthesized with various acidities, micropore structures, bulk porosities, and heteroatom substitutions. Therefore zeolites can meet the demands for a wide variety of reactions, especially for reactions that use feed streams with varying compositions (e.g. biomass, petroleum, etc.).  The use of lignocellulosic biomass as a source of renewable energy has gained traction in recent years due to the finite supply, environmental effects, geopolitics, and overall sustainability of fossil fuels. As the only source of renewable carbon on earth, biomass has been widely studied to meet the demands of a growing need for liquid renewable energy. Although non-catalytic, thermal conversion of solid lignocellulosic biomass to liquids can be achieved, the resulting product is often unstable, highly oxygenated, and subsequently a low quality fuel oil. With an appropriate catalyst, these products or reaction intermediates can be upgraded to valuable and stable fuels and chemicals mimicking those currently produced from petroleum resources. Thus, a catalyst is an essential part of the process of converting biomass to drop-in fuels and chemicals. This research addresses the innovative solutions to design and control zeolite catalyst properties to enhance the conversion of biomass feedstocks to value added chemicals and fuels. The results of altering the acidity, microporous structure, bulk porosity, and heteroatom substitution of ZSM-5 for biomass upgrading reactions are presented here. This first application of this work was the assessment of these various catalyst properties for the catalytic fast pyrolysis of lignin model compounds. It was determined that acidic, mesoporous, HZSM-5 was the most favorable catalyst for the production of aromatic liquid hydrocarbon fuels. The second application of this work was the synthesis of ZSM-5 with cerium incorporated within the framework. With detailed characterization and the use of well-studied model compound reactions, it was determined that cerium was indeed incorporated into the framework of the catalyst, yielding highly active sites to enhance the stability of oils derived from lignocellulosic biomass.