Abstract: The differential operant conditioning method reveals that workers of Myrmica sabuleti Meinert, 1861 distinguish colours from one another, as well as colours from greys. In high light intensity, these ants are slightly sensitive to red, sensitive to green, and highly sensitive to yellow and blue. In low light intensity, they are no longer sensitive to red, but sensitive to yellow and blue, and highly sensitive to green and violet. Moreover, these ants clearly perceive black objects under Uv light: They are thus sensitive to wavelengths shorter than those corresponding to violet.