A monolithic refractory structure includes: a monolithic refractory; a support body which supports the monolithic refractory; and a heat-resistant fiber support material which is buried in the monolithic refractory in a state of being connected to a support surface of the support body. The heat-resistant fiber support material includes a heat-resistant fiber rope which is formed of an inorganic fiber and extends along an X-axis direction perpendicular to the support surface, and a ratio L1/L2 of an X-axis direction length L1 of the heat-resistant fiber rope to an X-axis direction length L2 of the monolithic refractory is 0.35 or more and 0.95 or less.