This study was camed out during the seasons of 2003 and 2004 to study the effect of Humic acid and or K, B and Zn on leaf mineral content, berry set, leaf area, yield and bunch quality of Roomy Ahmar grapevines grown in a clay loam soil under surface irrigation system IA EL-Baramoon Experimental Farm, Dakahlia Governorate. Humic acid and or K, B and Zn were used at 5 %, 2 %, 0.2 % and 0.2 % respectìvely..K,8 and Zn are used as a foliar spray at three times (before bloom, after berry set and when berries reached about two thirds of their normal sìze.Whereas humic acid is u&d as soH treatments in the same times. Data reveal that all treatments significantly increased NPK, B and Zn content ¡n leaf petioles as compared to control, in the two seasons under study.Furthermore, all treatments, significantly increased berry set, average leaf area, yleki per vine bunch weight, number of berries/bunch, compactness coefficient, berry weight and size and juice volume of bernes. Moreover, alt treatments significantly increased total solub'e solids, SSC/acid ratio and tota' anthocyanin in berries akin. Yet, significantly decreased total acidity ¡n juice berries. Humic acid alone or with combination with K. B and Zn treatments presented more pronounced effect. From our study it was concluded that humic acid as soil applicat at 5 % enhances plant nutrition, increas leaf area., increased yield and improved bunch quality of Roomy Ahmar grapevines.