The sweet violet is a perennial that grows to between 3 and 10 centimetres in height. It has heart-shaped, dark green leaves, about 2 centimetres long, growing in a rosette at the base of the plant. The roots are creeping and send out runners. The flowers form at the top of the stem, separated from the leaves. The five petals are 15 millimetres across. Depending on the soil and amount of light, the flowers may be deep purple or blue to pinkish, or even yellow-white. Cultivated versions can be white or red.
The violet grows in woods, preferring the edges of forests and forest clearings, as well as in dry shrubby areas and damp and shady places. It is native to Europe and Asia.