A process for producing a 1.alpha.,3.beta.,24-trihydroxy-.DELTA..sup.5 -steroid represented by the formula (II): ##STR1## wherein R.sub.1 and R.sub.2, independently, represent a hyrogen atom, or R.sub.1 and R.sub.2 together form a single bond, R.sub.3 represents an unsubstituted or halogen-substituted lower alkyl, and R.sub.4 represents a hydrogen atom, hydroxy or a protected hydroxy, comprising reducing a 1.alpha.,2.alpha.-epoxy-.DELTA..sup.4,6 -3,24-dioxosteroid represented by the formula (I) ##STR2## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 have the same meanings as defined in formula (II), using an alkaline metal or alkaline earth metal and a proton donor in a solvent comprising ammonia or amine characterized in that at an early stage of the reaction, the 1.alpha.,2.alpha.-epoxy-.DELTA..sup.4,6 -3,24-dioxosteroid is reacted with the alkaline metal or alkaline earth metal in the presence of a proton acceptor, and then at a later stage of the reaction, a resulting intermediate product is reacted with the proton donor.