A fluid distribution valve which selectively distributes a fluid supplied from a fluid supply source (122, 132) to a plurality of flow channels, comprising: first and second branch pipes (73, 83) communicating with the fluid supply source (122, 132); and a valve body selectively closing either one of the two branch pipes (73, 83), and including a through hole allowing a circulation of the fluid into the second branch pipe from the fluid supply source (122, 132) in a case wherein the first branch pipe is closed, wherein while the valve body closes the first branch pipe in an initial state thereof, the valve body is displaced or deformed according to a pressure difference of the fluid in a first branch pipe side and a second branch pipe side when the fluid is supplied from the fluid supply source (122, 132), to thereby open the first branch pipe, and to close the through hole, further comprising an accumulator having a storage space communicating with the fluid supply source (122, 132) through the through hole in a case wherein the first branch pipe is in a closed state, and wherein the storage space is expanded by a pressure of the fluid when the fluid is supplied from the fluid supply source (122, 132), characterized in that the accumulator includes a cup-shaped elastic member defining one portion of the storage space; the elastic member includes a bottom portion having an end-rounded conical shape, and an annular opening edge portion continuing into the bottom portion; and while the bottom portion is in a state folded back inside the opening edge portion in an initial state of the elastic member, the state folded back is resolved by a pressure of the fluid when the fluid is supplied from the fluid supply source (122, 132). first and second branch pipes (73, 83) communicating with the fluid supply source (122, 132); and a valve body selectively closing either one of the two branch pipes (73, 83), and including a through hole allowing a circulation of the fluid into the second branch pipe from the fluid supply source (122, 132) in a case wherein the first branch pipe is closed, wherein while the valve body closes the first branch pipe in an initial state thereof, the valve body is displaced or deformed according to a pressure difference of the fluid in a first branch pipe side and a second branch pipe side when the fluid is supplied from the fluid supply source (122, 132), to thereby open the first branch pipe, and to close the through hole, further comprising an accumulator having a storage space communicating with the fluid supply source (122, 132) through the through hole in a case wherein the first branch pipe is in a closed state, and wherein the storage space is expanded by a pressure of the fluid when the fluid is supplied from the fluid supply source (122, 132), characterized in that the accumulator includes a cup-shaped elastic member defining one portion of the storage space; the elastic member includes a bottom portion having an end-rounded conical shape, and an annular opening edge portion continuing into the bottom portion; and while the bottom portion is in a state folded back inside the opening edge portion in an initial state of the elastic member, the state folded back is resolved by a pressure of the fluid when the fluid is supplied from the fluid supply source (122, 132).