Ayurvedic medicines are basically derived from the Vedic literature and plants of family Fabaceae have special importance in the Ayurvedic medicines.The family Fabaceae popularly known as legumes, is the third largest order of seed-plants containing about 600 genera with 12,000 species. They are usually arranged in three well defined sub families and they are Papilionaceae, Caesalpiniaceae and Mimosaceae.

          Some of the important medicinal plantsof sub family Papilionaceae include Abrus precatorius Linn., Alhagi camelorum Linn.,Alhagi murorum, A. pseudalhagi Linn., Arachis hypogaea Linn., Alysicarpus lyagfolius Wight And Arn., Alysicarpus nummularifolius DC., A.rugosus DC., A.vaginalis DC., Astragalus hamosus Linn.,A. multiceps Wall., A. strobiliferus Royle., A. tribuloides Del., Atylosia scarabaeoides Benth., Butea monosperma O. Kuntze., Butea superba Roxb., Cajanus indicus Spreng., Canavalia ensiformis DC., Cicer arintinum Linn., Clitoriaternatea Linn., Colutea nepalensisSims., Crotolaria alata Ham., C. albidaHeyne, C. burhia Ham., C. fulva Roxb., C. junea Linn., C. prostrataRottl., C. retusa Linn., C,sericea Retz., C. striata DC., C. trifoliastrumWills., C. versucosa, Cyamopsis tetragonoloba Taub., Cylista scariosa Roxb., Dalbergia lancelaria Linn., D. latifolia Roxb., D. multiflora Heyne, D. sissiRoxb., D. spinosa Roxb., D.tamarindifolia  Roxb., D.volubilisRoxb., Derris indica Benth., Derrisscandens Benth, D. uliginosa Benth, Desmodium gangeticum DC., D.heterophyllum DC., D.lasiocarpum DC., D. polycarpum DC., D. pulchellum Benth., D. retroflexumDC., D. scalpe DC., D. tiliafolium G. Don, D. triflorum DC., Dolichos biflorus Linn., D. falcatusKlein., D. lablab Linn., Erythrina indica Lam., E. ovalifolia Roxb.,E. stricta Roxb., E. suberosa Roxb., Fleminga chappar Ham., F.congestaRoxb., F. nana Roxb., F. strobilifera R.Br, F. tuberosa Dalz., Glycyrrhiza glabra Linn., Glycine soja Sieb.&Zucc., Indigofera  argentea Linn., I.aspalathoides Vahl., I . gerardiana R. Grah., I . glabra Linn., I . glandulosa Willd., I .hirsute Linn., I . linifolia, Retz.,I . oblongifolia Forsk., I . pulchella Roxb., I . tinctoriaLinn., I . trifoliata, I. trito Linn. Fil., Lens esculenta Moench ., Melilot indica All, M. officinalis Lam., Mucuna capitata Sweet, M. giganteaDC., M. monosperma DC., M . prurita Hook., Ormocarpum sennoides ., Ougeina dalbergioides Benth ., Pachyrhizus angulatus Rich., Phaseolus aconitifolius Jacq ., P. adenanthus Meyer.,Phaseolus lunatus Linn., P . mungo, P. radiatus Linn. , P. trilobusAit ., P.vulagris Linn., Pisum sativumLinn., Pongamia glabra Vent., Pseudarthria viscida W. and A., Psoralea corylifolia Linn., Pterocarpus indicus Willd., P. marsupium Roxb., P. santalinusLinn. fil., Pueraria tuberosa DC., Rhynchosia minima DC., Sesbania aculeatePoir, Sesbania aegyptiaca Poir, S. grandifloraPers., Sophora tomentosa Linn., Spatholobus roxburghii Benth ., Taverniera cuneifolia Arn., Tephrosia petrosa  Blatter and Hallberg ., T.purpurea Pers, Tephrosia villosa Pers., Teramnus labialis Spreng ., Trigonella foenum –graecum Linn., T.occulta Del., T. polycerata Linn., Urariapicta Desv ., Vicia faba Linn., Vicia sativa Linn., Vigna catiang Walp., Zornia diphylla Pers.,

          Some of the important medicinal plants of sub family Caesalpiniaceae includes Afzelia bijuga A. Gray, Afzelia bijuga A. Gray, Bauhinia malabarica Roxb., B.purpurea Linn., B. racemosa Lam.,B.retusa Roxb., B. rufescens Lam., Bauhinia tomentosa Linn., B. vahliiWight and Arn, B. variegata Linn ., Caesalpinia bonduc Roxb., C.bonducella Flem., C.coriaria Willd., C.digynaRottl., C.nuga Ait., C.pulcherrima Swartz., C.sappan Linn ., C.sepiaria Roxb., Cassia absus Linn., Cassia alata Linn., C. auriculataLinn ., C. fistula Linn ., C.glaucaLam., Cassia mimosoides Linn., C.obovata, Collad ., C.obtusifolia Linn., C.occidentalis Linn., C.sopheraLinn., Cassia tora Linn., Ceratonia siliquaLinn., Cynometra caulifloraLinn., Cynometra polyandra Roxb., Cynometra ramiflora Linn., Gleditschia sinensis Linn., Haematoxylon campechinanum Linn., Hardwickia pinnata Roxb., Humboldtia vahliana Wight., Poinciana elata Linn., Saraca indica Linn., Tamarindus indica Linn., Wagatea spicata Dalz.

          Some of the important medicinal plants of sub family Mimosaceae includes Acacia arabica Willd ., A. catechu Willd., A. concinnaDC., A. farnesiana Willd., A. ferruginea DC., A. leucophloea Willd., A. modesta Wall., A. pennata Willd., A. senegalWilld., Albizzia amara Boivin., A. julibrissin Durazz., Albizzia lebbek Benth., A. odaratissima Benth., A. ProceraBenth., A. stipulata Boivirs., Dichrostachyscinerra Wight and Arn., Entadascandens Benth., Leucaena glauca Benth.,Mimosa hamata Willd., Mimosa pudica Linn., Mimosa rubicaulis Lam., Neptunia oleracea Lour., Parkia roxburghii G.Don., Pithecolobium bigeninum Mart., P.dulce Benth., Prosopis spicigera Linn.,Xylia dolabriformis Benth.

          The Cassia belonging to sub family Caesalpiniaceae is represented by a large number of species which includes Cassia alata Linn., Cassia auriculata Linn., Cassia didymobotryaFresen., Cassia fistula Linn., Cassia floribunda Cav. syn.C.laevigata Willd., Cassia grandis Linn., Cassia italica (Mill.) syn.C.obovataCollad., Cassia javanika Linn., Cassia mimosoides Linn., Cassia multijuga Rich.,Cassia nigricans Vahl., Cassia nodosa Buch. Ham. ex Roxb., Cassia obtusifolia Linn., Cassia pumila.

          Cassia senna Vahl. is very important plant of Ayurvedic medicines. The plant is avariable, branching, erect shrub and it is highly drought resistant crop andsuitable for desert. It is largely cultivated on marginal lands in a 10,000ha., both as rain-fed and irrigated crop, mainly in Tamil Nadu, where it is nowgrown principally as a cash-crop in Tirunelveli, Ramanathapuram,Tiruchchirappalli and Madurai districts and to a lesser extent in Salemdistrict.