Provided is a uracil compound or a salt thereof, which has potent human dUTPase inhibitory activity and is useful as, for example, an antitumor drug.A uracil compound represented by the general formula (I) or a salt thereof: wherein n represents an integer of 1 to 3; X represents a bond, an oxygen atom, a sulfur atom, or the like; Y represents a linear or branched alkylene group having 1 to 8 carbon atoms, or the like; and Z represents —SO2NR1R2 or —NR3SO2—R4, wherein R1 and R2 each represent an alkyl group having 1 to 6 carbon atoms, an aralkyl group which is optionally substituted, or the like; R3 represents an alkyl group having 1 to 6 carbon atoms, or the like; and R4 represents an aromatic hydrocarbon group, an unsaturated heterocyclic group, or the like.