[2] The black-capped bulbul was formally described in 1789 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae.

[5] Gmelin based his description on the "yellow-breasted fly-catcher" from Sri Lanka that had been described and illustrated in 1776 by the English naturalist Peter Brown.

[7] A molecular phylogenetic study of the bulbul family published in 2017 found that Pycnonotus was polyphyletic.

[8] In the revision to the generic classification the black-capped bulbul and four other species were moved from Pycnonotus to Rubigula.

[10] The black-capped bulbul is virtually crestless and has a yellow throat and brownish eyes.