The palladium‐catalyzed cyclopropanation of strained alkenes with 3‐trimethylsilyl‐ or 3‐pinacolatoboryl‐1‐arylallyl acetate derivatives is described. This reaction gives cyclopropanation products in good to high yields with a single diastereomer, and the key step is likely to involve the formation of a palladacyclobutene complex from the α‐trimethylsilyl‐ or α‐pinacolatoboryl‐σ‐allylpalladium complex