An emergency detachment device of a fluid handling device, the emergency detachment device being configured so that a first coupler and second coupler , each of which being provided with a valve for shutting off the passage of fluid that is being passed within handling piping and preventing the fluid from flowing out to the exterior, are detachably connected by a connection mechanism to allow emergency detachment to be performed, and the emergency detachment device being configured so that, in an emergency, the valves of each of the first coupler and the second coupler operate to enter a closed-valve state and shut off passage of the fluid, the connection mechanism disestablishes the connection between the first coupler and the second coupler , and the first coupler and the second coupler separate, wherein the emergency detachment device of a fluid handling device is characterized in that : each of the first coupler and the second coupler is formed in a vacuum dual-layer structure, in which an inner pipe section through which the fluid passes is covered by an outer pipe section , and in which the space between the inner pipe section and the outer pipe section is placed in a vacuum state, and two of the valves are provided in series within the inner pipe section in the direction in which the fluid passes; the emergency detachment device of a fluid handling device is provided with a remaining-fluid-transferring mechanism for causing residual fluid that remains on the coupler-opening side of second valves to be transferred into the inner pipe sections , which are further inward than the second valves , after the second valves have both assumed the closed-valve state during emergency detachment, the second valves being, among the two valves provided in series within the inner pipe section , provided further inward than first valves , which are provided on the coupler-opening sides; the remaining-fluid-transferring mechanism is configured so that a gas for fluid transfer is introduced into a residual fluid section, in which the residual fluid remains, via a section for introduction of gas for fluid transfer provided in the inner pipe section on the coupler-opening side of the second valve , the residual fluid is discharged from the residual fluid section, and the residual fluid is transferred via a transfer piping section into the inner pipe section provided further inward than the second valve of one or both of the first coupler and the second coupler ; and in an emergency detachment action completion state in which the first valves and the second valves are in the closed-valve state and the first coupler and the second coupler are separated, the space sections partitioned and formed by each of the first valves and the second valves in the closed-valve state in the first coupler and the second coupler become heat insulation sections , heat conduction to the inner pipe sections and the second valves is reduced to the extent possible by the heat insulation sections and vacuum sections between the inner pipe sections and the outer pipe sections , evaporation of fluid within the inner pipe sections is prevented, the conduction of coldness of the fluid to the outer pipe sections and the first valves is reduced to the extent possible, and the coupler surfaces are prevented from reaching extremely low temperatures. <EOS>