HYDRAULIC COMPOSITION ADMIXTURE

There is provided an admixture for a hydraulic composition that suppresses the blackening resulting from the colored fine particles, and suppresses retardation of setting, bleeding, and a decrease in initial strength, in addition exhibits excellent water-reducing ability. An admixture for a hydraulic composition comprising a polycondensation product P containing a copolymer prepared by polycondensation of a monomer mixture containing compounds A to C of the following Formulae (A) to (C); and a polycarboxylic acid-based polymer Q including a structural unit having an amino group and an imino group, and/or a structural unit having an amino group, an imino group, and an amido group: (C) R3-CHO, HO(CH2O)rH or (CH2O)3(wherein R1is a hydrogen atom, an alkyl group, or an alkenyl group; A1O is a C2-4alkylene oxide group; p is a number of 1 to 300; and X is a hydrogen atom, an alkyl group, or an acyl group; R2is an alkyl group or an alkenyl group; A2O is a C2-4alkylene oxide group; q is a number of 1 to 300; and Y1is a phosphate ester group; and R3is a hydrogen atom, a carboxy group, an alkyl group, an alkenyl group, a phenyl group, a naphthyl group, or a heterocyclic group; and r is a number of 1 to 100).