A microchemical system, including two micromixers and a delay, loop, is specially designed to carry out the chlorohydrination of allyl chloride with chlorine in water. Chlorine is dissolved in water in the first micromixer and then reacts with allyl chloride to produce dichloropropanol in the second micromixer. The reaction can be accomplished in the delay loop with a residence time less than 10 s and the selectivity higher than 98%. A multistage strategy which connects several microchemical units in series has been developed and demonstrated. The dichloropropanol concentration higher than 6 wt % with the selectivity higher than 96% can be successfully reached using this strategy. The results show that low temperature and high pressure could greatly improve the microreaction performance. In contrast to the conventional reaction process, the microreaction process has the advantages for higher yield, higher dichloropropanol concentration, less water waste, and lower energy consumption. Moreover, the new process Could make the reaction process employing chlorine more controllable and safe.