The utility model relates to a descale valve valve barrel dismounting device, including a type support, pull rod, crossbeam and 2 jack catchs, the width and valve body diameter phase -match of door type support, open at the center of door type bracket rails length has the through -hole that link up from top to bottom, and pull rod upper portion threaded connection has the nut, and diameter of nut is greater than type bracket rails's a diameter of hole, and it is fixed with the mid point of crossbeam length that the pull rod lower extreme passes the through -hole, the jack catch is the chair column structure to back -to -back form sets up in the both ends of crossbeam, and the seat support bottom surface of chair form jack catch offsets with the upper surface of crossbeam, and seat support seat face offsets with the valve barrel bottom surface, the ultimate range after the jack catch is accomplished with the crossbeam assembly between 2 jack catchs and the external diameter phase -match of valve barrel. The utility model discloses can dismantle fast, safely and descale the valve valve barrel, effectively avoid prior art to utilize the jack to dismantle the valve barrel in -process and harm the phenomenon of valve body and valve barrel owing to take place the incline, have the simple installation laborsaving, adjust convenient, the compact advantage of simple structure.