The invention discloses a vapor and liquid two-phase fluid mixing condensation device. The vapor and liquid two-phase fluid mixing condensation device comprises an inner cylinder and an outer cylinder, wherein the first end of the inner cylinder is communicated with a vapor phase pipe and the second end of the inner cylinder is closed; the outer cylinder is sheathed at the external part of the inner cylinder, the first end of the outer cylinder is closed and the second end of the outer cylinder is communicated with a hot water pipe; a liquid phase fluid pipe which is communicated with the internal part of the outer cylinder is arranged on one side of the outer cylinder; a hole-free area and a hole area are arranged on the outer wall of the inner cylinder between the liquid phase fluid pipe and the second end of the inner cylinder, the hole-free area isolates liquid phase fluid and the vapor phase through the side wall of the inner cylinder to enable the liquid phase fluid and the vapor phase to be in preliminary indirect contact, a plurality of through holes which are communicated with the inner cylinder and the outer cylinder are formed in the hole area, and the through holes enable the liquid phase fluid and the vapor phase to be in direct contact and be mixed. The vapor and liquid two-phase fluid mixing condensation device disclosed by the invention has the advantages that the structure is simple and the mixing condensation effect is remarkable.