A coloring matter absorbing a near-infrared ray which comprises a diimonium salt containing a sulfonimide as an anion moiety, represented by the general formula (1): ##STR00001## wherein R may be the same or different and represents a moiety selected from the group consisting of an alkyl group, a halogenated alkyl group, a cyanoalkyl group, an aryl group, a hydroxyl group, a phenyl group, and a phenylalkylene group, and R.sup.1 and R.sup.2 may be the same or different and each represent a fluoroalkyl group, or together form a fluoroalkylene group.The coloring matter absorbing a near-infrared ray is excellent in the resistance to heat and moisture, and thus exhibits an ability of absorbing a near-infrared ray not lowering for a long period of time. A filter for cutting off a near-infrared ray manufactured by using the coloring matter can be advantageously used for wide applications such as a plasma display panel, an optical lens, a glass for an automobile, and a glass for a building material, due to its excellent resistance to heat and moisture.