堇菜科是属于金虎尾目（旧属堇菜目）的一类植物，大多为草本，有少数为灌木，花两性，单叶互生，有长叶柄。花瓣为5，不整齐，下面一瓣比其他瓣较大。

堇菜科植物有22属，大约900多种，广泛分布在全世界各地的温带和热带地区，中国分布有4属：鼠鞭草属（Hybanthus）；鳞隔堇属（Scyphellandra）；三角车属（Rinorea）和堇菜属（Viola），大约130种。

Violaceae /vaɪəˈleɪsiː/ (including Alsodeiaceae J.G.Agardh, Leoniaceae DC. and Retrosepalaceae Dulac) is a family of flowering plants consisting of about 800 species in 25 genera. It takes its name from the genus Viola, the violets and pansies.

Older classifications such as the Cronquist system placed Violaceae in an order named after it, the Violales. However, newer classifications such as that of the Angiosperm Phylogeny Group locate it in the Malpighiales.