Abstract: Background: Flavonoids are taxonomically important and have popular characters for chemosystematics studies by the reason universal presence in vascular plants. Also they are active principles of medicinal plants, exhibit pharmacological effects and contribute to human health. Flavonoids have roles in plant ecological adaptation, pollination, distribution and as attractant/deterrent factor for pollinator or pests. This study shows the flower flavonoid patterns of Convolvulus L. populations from Markazi Province, Iran for revealing flavonoids role in Convolvulaceae chemotaxonomy. This is a novel report on Convolvulus flower flavonoid patterns and also some of flavonoid types in C. arvensis were identified for the first time. Materials and Methods: Phytochemical studies on 12 collected Convolvulus populations from 4 species (C. arvensis , C. commutatus , C . lineatus and C. pilosellaefolius ) were done using two-dimensional paper chromatography (2-DPC) and Thin Layer Chromatography (TLC). Voucher specimens of each species were prepared for reference as herbarium vouchers. Results: Results indicated that the flowers contained flavonoid sulfates and flavones C and C-/O glycosides, apigenin, chrysin, genistein, hesperidin, isorhamnetin, kaempferol, luteolin, myricetin, naringenin, quercetin, rhamnetin, rutin, tricine and vitexin. Morin was not found in any of the taxa and kaempferol, hesperidin and naringenin was the most found flavonoids in order. There were not any aglycones in the studied populations. Populations of C. commutatus had the most number of total flavonoids and C. lineatus had the least one. Tricine was the rare flavonoid in all of C. arvensis populations and rhamnetin was the rare flavonoid in all of C. commutatus populations, too. Conclusion: It seems that kaempferol concentration pattern would be useful for separation of C. arvensis from the other Convolvulus species and also, naringenin concentration pattern would be useful for the separation of C. commutatus from rest.