The utility model belongs to the technical field of the chemical industry equipment and specifically relates to a horizontal extrinsic cycle atomizing ethoxy - reaction unit. The device includes reactor, collecting vat, material heat exchanger and circulating pump, wherein: the reactor includes barrel, principal goods material distributing pipe, vice material distributing pipe, initiator nozzle and EO nozzle, the center axial of barrel sets up principal goods material distributing pipe, vice material distributing pipe symmetric distribution on the internal face of barrel, it has the 3 -8 root, the initiator nozzle evenly sets up on principal goods material distributing pipe and vice material distributing pipe, the EO nozzle evenly sets up on barrel upper portion. The utility model discloses it is big to install effective reaction space, and unit volume's area of contact is big, and the atomizing flow field is even, does not have the reaction dead angle, is favorable to improving the reaction rate, increase output and promotion product quality.