The present investigation was carried out during winter of the consecutive seasons (2018/2019 and 2019/2020) on 9 year old Flame Seedless grapevines grown in a private vineyard at Sharkia Governorate, Egypt. Garlic (Balady cv) was intercropped with grapevines (Flame Seedless cv) on dripper irrigation lines, as a try to reduce numbers of phytonematodes in grapevine soil. For grapevines, the obtained results referred that intercropping insignificantly (P≤0.05) increased number of berries/bunch, weight of 100 berries and berry firmness, separation force, total soluble solids percentage, anthocyanin content and yield/ vine as well as bunch weight and width, berry length, berry diameter and berry shape index compared to sole grapevines. For garlic (Balady cv), the achieved results pointed out that plant height, number of leaves/plant, leaf fresh weight/ plant, nick diameter as well as bulb diameter, height and weight/ plant insignificantly decreased when garlic intercropped with grapevines compared to control. Competition indices; i.e., land equivalent ratio (LER), area time equivalent ratio (ATER) and land utilization efficiency (LUE) showed that, intercropping garlic with grapevines was more efficient than sole cropping system. Aggressively estimation demonstrated that grapevines were dominant advantages while garlic was dominated. Moreover, intercropping garlic (Balady cv) with grapevines was obviously decreased population density of phytonematodes infesting grapevine orchard. Generally, garlic together with other biocontrol agents in grapevine orchards has the potential to be an efficient and environmentally agricultural management method to reduce numbers of plant parasitic nematodes. Keywords: Grapevines, garlic, intercropping, yield, growth, competitive indices, plant parasitic nematodes.