• Viola Evans, 1953 [Family: Hesperiidae]
• Viola Linnaeus, 1753 [Family: Violaceae]
• Viola aberrans Greene accepted as Viola conjugens Greene
• Viola abundans House accepted as Viola sagittata Ait.
• Viola adunca Sm.
• Viola aduncoides A. & D. Löve accepted as Viola adunca Sm.
• Viola affinis Le Conte
• Viola agellae Pollard
• Viola alicoides Hayward, 1938
• Viola alicus Schaus, 1902
• Viola angellae Pollard accepted as Viola bernardii Greene
• Viola appalachiensis Henry
• Viola arvensis Murr.
• Viola aurea Kellogg
• Viola bakeri Greene
• Viola beckwithii Torr. & Gray
• Viola bellidifolia Greene accepted as Viola adunca Sm.
• Viola bernardii Greene
• Viola bicolor Pursh
• Viola biflora Linnaeus
• Viola bissellii House
• Viola biternata Greene accepted as Viola sheltonii Torr.
• Viola blanda Willd.
• Viola brauniae Grover ex Cooperrider
• Viola brittoniana Pollard
• Viola caesariensis House accepted as Viola mistura House
• Viola californica M.S. Baker
• Viola canadensis Linnaeus
• Viola canina Linnaeus
• Viola cascadensis M.S. Baker accepted as Viola adunca Sm.
• Viola cestrica House accepted as Viola sagittata Ait.
• Viola chalcosperma Brainerd accepted as Viola affinis Le Conte
• Viola chamissoniana Gingins
• Viola champlainensis House accepted as Viola sororia Willd.
• Viola charlestonensis M.S. Baker & J.C. Clausen ex Clokey
• Viola charlestownensis M.S. Baker & J. Clausen
• Viola chinensis G. Don accepted as Viola patrinii DC.
• Viola clauseniana Baker
• Viola columbiana House accepted as Viola filicetorum Greene
• Viola concolor T.F. Forst. accepted as Hybanthus concolor (T.F. Forst.) Spreng.
• Viola conjugens Greene
• Viola conjuncta Riley, 1929
• Viola consobrina House
• Viola consocia House
• Viola consona House accepted as Viola filicetorum Greene
• Viola conspersa Reichenb.
• Viola conturbata House accepted as Viola bissellii House
• Viola convicta House accepted as Viola mistura House
• Viola cooperrideri H.E. Ballard
• Viola cordifolia (Nutt.) Schwein.
• Viola cucullata Ait.
• Viola cuneata S. Wats.
• Viola curtisii E. Forster
• Viola davisii House
• Viola dimissa House accepted as Viola redacta House
• Viola discors House accepted as Viola slavinii House
• Viola dissena House
• Viola dissensa House accepted as Viola hollickii House
• Viola dissita House accepted as Viola ravida House
• Viola douglasii Steud.
• Viola dowelliana House accepted as Viola consobrina House
• Viola eamesii House
• Viola eclipes H.E. Ballard
• Viola egglestonii Brainerd
• Viola egra Evans, 1953
• Viola emarginata (Nutt.) Le Conte accepted as Viola sagittata Ait.
• Viola epipsila Ledeb.
• Viola epipsiloides A. & D. Löve accepted as Viola epipsila Ledeb.
• Viola eriocarpon (Nutt.) Schwein. accepted as Viola pubescens Ait.
• Viola erratica House accepted as Viola sagittata Ait.
• Viola esculenta Ell. accepted as Viola palmata Linnaeus
• Viola falcata Greene accepted as Viola palmata Linnaeus
• Viola fernaldii House accepted as Viola conjugens Greene
• Viola festata House accepted as Viola palmata Linnaeus
• Viola filicetorum Greene
• Viola fimbriatula Sm. accepted as Viola sagittata Ait.
• Viola flettii Piper
• Viola floridana Brainerd accepted as Viola sororia Willd.
• Viola frank-smithii N. Holmgren
• Viola glabella Nutt.
• Viola greenei House accepted as Viola conjugens Greene
• Viola greenmani House
• Viola greenmanii House accepted as Viola conjugens Greene
• Viola guadalupensis A. Powell & B. Wauer
• Viola hallii Gray
• Viola hastata Michx.
• Viola hecata Hayward, 1947
• Viola helena C.N. Forbes & Lydgate
• Viola helenae Forbes & Lydgate
• Viola hermione Hayward, 1938
• Viola herse Hayward, 1938
• Viola hirsutula Brainerd
• Viola hirta Linnaeus
• Viola hollickii House
• Viola holmiana House accepted as Viola mulfordiae Pollard
• Viola howellii Gray
• Viola incognita Brainerd accepted as Viola blanda Willd.
• Viola insessa House accepted as Viola sororia Willd.
• Viola insolita House
• Viola kauaensis Gray