A new distinct cultivar of Euphorbia milii plant named `2004-8`, characterized by its compact, globular, upright plant habit; very dense and bushy plant form, mainly due to upright stems; large number of long stemmed flowers per plant due to 6 to 9 cm in length yellow-green peduncles, with gray-brown mottling towards base; striking color combinations of light red (pink) bracts (when opening RHS 36C, RHS 54A when fully opened) and staminate cyathia with yellow glands (RHS 9A) to green-yellow glands (RHS 1C) during development; and large, obovate, leaves (yellow-green, RHS 144A when young and green, RHS 137A when mature).