PURPOSE: To obtain a composition which can dissolve a large amount of sulfur at a high rate and reduced in the rate of loss of catalytic activity during storage by mixing a specified organic di- or poly-sulfide with a catalytically effective amount of an amine/mercaptan mixture and a stabilizer.

CONSTITUTION: This composition is prepared by mixing an organic di or poly- sulfide represented by the formula: R1SSASR2 (wherein R1 and R2 are each an alkyl, aryl, alkaryl, alkoxyalkyl or hydroxyalkyl group with a 1-24C alkyl moiety; and A is 0-3) with a catalytically effective amount of a mixture comprising a polyamine desirably represented by the formula (wherein R6 to R12 are each H, an alkyl, an aryl, a cycloalkyl, an alkaryl or the like; and X is 0-25) and a mercaptan desirably represented by the formula: R30SH (wherein R30 is an alkyl, an aryl, an alkaryl, an alkoxyalkyl or a hydroxyalkyl) and a stabilizer used for inhibiting the loss of catalytic activity during storage and desirably comprising a substituted phenol.