Abstract: A dyed union knit fabric comprised of at least a polyurethane elastic fiber containing a chlorine-induced degradation inhibitor in a proportion of 0.5-4.5 weight % relative to the weight of the fiber, and a polyamide fiber and/or a cation dyeable polyester fiber, which has been dyed with mixed dyes of acid dyes, dispersion dyes, metal-complex dyes, reactive dyes and direct dyes, and markedly improved in resistance to chlorine-induced change in shade by allowing to contain at least one compound having a reaction amount of chlorine of 50 milliequivalent per gram or more, specifically one member of mono- and/or polyhydroxybenzene derivatives in a proportion of 0.1-20 % relative to the weight of the fiber; and a method for manufacturing same. According to the present invention, excellent resistance to chlorine-induced change in shade as well as chlorine-induced degradation can be afforded to the dyed union knit fabric.