Studies on the Mechanism of the Chlorohydrination of Olefins We studied the rate‐determining and the product‐determining steps of the chlorohydrination of olefins with Cl2/H2O and HOCl. In competitive kinetic experiments with 3‐ethylpent‐2‐ene and cyclohexene we determined the relative rate constants krel = 1,5 (with Cl2/H2O) and krel = ∞ (with HOCl). This shows that the rate‐determining steps of the chlorohydrination with Cl2/H2O and with HOCl are different. In order to investigate the product‐determining steps we determined the proportion of alkyl‐(2‐chloroethyl)‐ethers 3 and ethylene chlorohydrine 2 in the reaction of ethylene with Cl2 and with HOCl in alcohol/water‐mixtures. The proportion of both the reaction products 3/2 was independent of the chlorinating agent used. Also the proportion of MARKOVNIKOV and anti‐MARKOVNIKOV products in the chlorohydrination of propylene with Cl2/H2O or HOCl was independent of the type of chlorinating agent. In the chlorohydrination of cyclohexene both agents (Cl2/H2O and HOCl) yielded only the trans‐chlorohydrine. From the results obtained it may be concluded that the product‐determining step of chlorohydrination is the same for both the chlorinating agents studied.