The present invention relates to a trisazo compound represented by the following formula (1) or a salt thereof, The formula (1) wherein, the group A is a substituted phenyl group, the group B and the group C are substituted para-phenylene groups, R1 represents a C1 to C4 alkyl group which may be substituted by a carboxy group, a phenyl group which may be substituted by a sulfo group, or a carboxy group, R2 represents a cyano group, a carbamoyl group or a carboxy group, each of R3 and R4 independently represents a hydrogen atom, a methyl group, a chlorine atom or a sulfo group, respectively and a water-based black ink composition containing said compound; said compound has high solubility in a medium where the main component is water, its aqueous solution having a high concentration and ink are stable when stored for a long period of time, black-recorded images with it can be provided where both light fastness and ozone gas fastness of the printed images are excellent.