A sensitive method coupling high-performance liquid chromatography (HPLC) with diode –array detector (DAD) and electrospray ionization mass spectrometry (MS) was optimized for separation, identification, and quantification of cinnamic acid derivatives in Cichorium intybus seed and its extract. Cinnamic acid derivatives such as chlorogenic acid, caffeic acid and Chicoric acid were quantified using respective standards. Apart from 4-o-Caffeoylqunic acid, other cinnamic acid derivative such as 3-o-caffeoylquinic acid was also identified and quantified by UV and MS/MS spectra and calculated as total caffeoylquinic acids using 4-o-caffeoylqunic acid as standard in the seed and its extract. Other cinnamic acid derivatives such as 1,3-dicaffeoylqunic acid, 1,4-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid, 3, 4-dicaffeoylquinic acid, dicaffeoylquinic acid-1 and dicaffeoylquinic acid-2 (two unknown) were identified and quantified by UV and MS spectra and calculated as total dicaffeoylquinic acids using chlorogenic acid standard in the seed and its extract. The total cinnamic acids were quantified by calculating the sum of chlorogenic acid, caffeic acid, chicoric acid, total caffeoylquinic acids(4-o-caffeoylquinic acid and 3-o-caffeoylqunic acid) and total dicaffeoyl-quinic acids(1,3-dicaffeoylqunic acid, 1,4-dicaffeoylquinic acid, 3,5-dicaffeoyl-quinic acid, 3, 4-dicaffeoylquinic acid, dicaffeoylquinic acid-1 and dicaffeoyl-quinic acid-2). The Phytochemical screening of C. intybus seed and its extract revealed that this plant is a rich source of cinnamic acid derivatives so, these markers (cinnamic acid derivatives) can used for routine quality control of Cichorium intybus seed and its extract.