In this work, the protecting-group-free total synthesis and stereochemical assignment of (-)-boscartin F have been reported. The key steps, including Sharpless asymmetric epoxidation, I2-mediated iodoetherification, aldol reaction, and ring-closing metathesis, allowed for rapid and highly stereoselective access to boscartin F. In addition, single-crystal X-ray crystallographic analysis of the semicarbazone derivative 22 confirmed the stereochemistry of boscartin F.