The term 'phenolics' refers to a vast array of biologically active compounds ubiquitous in plants, many of which have been used in traditional medicine for thousands of years. Umbelliferone, psoralen, and eugenol are widely occurring phenolic compounds of plant origin, for which many biological activities against chronic diseases have been reported. A simple HPTLC method has been developed for the simultaneous quantification of umbelliferone, psoralen, and eugenol. These three compounds were quantified in the dried fruit pulp of Aegle marmelos and in the fruit of Trachyspermum ammi and Foeniculam vulgare. The technique enables rapid and sensitive simultaneous analysis in different samples. The method was validated for precision, repeatability, and accuracy in accordance with ICH guidelines. The accuracy of the method was checked by a recovery study conducted at three different levels and the average percentage recovery was found to be 98.88% for umbelliferone, 100.104% for psoralen, and 99.33% for eugenol. The proposed HPTLC method for the simultaneous quantification of umbelliferone, psoralen, and eugenol was found to be simple, precise, specific, sensitive, and accurate. It can be used for routine quality control of herbal raw materials as well as formulations containing any or all of these compounds.