The present invention relates to a black dye composition, comprising: (a) a compound of the following formula (I), ##STR00001## (b) a compound of the following formula (II), ##STR00002## (c) a compound of the following formula (III), ##STR00003## wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are defined the same as the specification. The present invention also relates to a black ink composition afforded from the aforementioned black dye composition. The black ink composition of the present invention is suitable for paper ink-jet printing, and exhibits the properties of good light-fastness, high color strength, solubility, and fine fluency of ink.