Monteverdia ilicifolia is a native Brazilian plant with a rich ethnopharmacological background. Popularly known as “espinheira-santa”, the species is widely used due to its anti-inflammatory, gastroprotective and anti-cancer activities. Those biological potential comes from its flavonoids, tannins and triterpenes including quinonemethide triterpenes (QMTs). Friedelin is the only triterpene in the isoprenoid biosynthesis with a ketone group at C-3, instead of an alcohol. In addition, friedelin is the precursor of the QMTs (celastrol, pristimerin and maytenin). Despite their potential, those metabolites are produced in small amount in the host3. A way to increase the production is to understand friedelin synthase activity and improve its production in a heterologous organism such as yeast. The aim of this work was to evaluate the production of the wild friedelin synthase (FRS) in Saccharomyces cerevisiae and some key enzyme mutants. We selected key positions for the site-directed mutations in the primary structure, including the residues Phe-183, Cys-369, Asp-484 and Trp-612. In comparison with the wild enzyme, the mutation Phe-183-Leu resulted in an increase in the production of friedelin and also the production of α-amyrin and β-amyrin. However, the mutation Cys-369-Ala showed a decrease in the production of the target triterpene, while the mutations Asp-484-Glu and Trp-612-Phe did not produce any amount of friedelin.