Plant natural products (PNPs) are a major source of substances used in industry,agriculture, and traditional or modern medicine. Traditionally, these chemicals are extracted from plantation agriculture with a significant cost in land, energy, and water. In response to these challenges, synthetic biology and heterologous biosynthesis have emerged to produce these valuable compounds in more sustainable and efficient industrial microorganisms, such as baker’s yeast Saccharomyces cerevisiae. Recent advances in natural product pathway elucidation have uncovered many large and complicated plant pathways that contain 10–30 genes for the biosynthesis of structurally complex, valuable natural products. However, the ability to reconstruct ultralong pathways efficiently in yeast does not match the increasing demand for valuable plant natural product biomanufacturing. Furthermore, the characterization of newly discovered natural product biosynthetic pathways from medicinal plants is challenging and laborious due to the experimental burdens of validating individual genes from potentially ultra-long biosynthetic pathways. To resolve the above problems, in this dissertation the development andoptimization of a CRISPR-mediated gene integration system with the necessary workflow in Saccharomyces cerevisiae that enables fast and efficient biosynthetic pathway integration have been presented. By combining these advances with parallelized multigene characterization, this integration system has further been developed into a robust strategy for the efficient characterization of entire biosynthetic pathways from medicinal plants.