Abstract: A process for the synthesis of Cannabidiol of formula (1): (1) is herein disclosed. The process comprises contacting a solution [solution (S1)] of (+)-p-mentha-diene-3-ol of formula (4) (4) or an ester thereof and olivetol of formula (3): (3) with a solution [solution (S2)] of a non-supported Lewis acid in a continuous flow reactor and treatment of the resulting mixture with a basic solution. The process offers the advantage that it can be conveniently carried out on an industrial scale while avoiding the formation of abnormal CBD and THC (?9-tetrahydrocannabinol).