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Persian walnut, Juglans regia L., is a long-lived, wind-pollinated and deciduous tree, which produces large, woody, shelled and edible nuts. J. regia is one of the most economically important cultivated species for timber and nutritious nuts. Its nuts have medicinal importance for human health by high antioxidant capacity. J. regia has been planted in Northern Vietnam for decades. In this study, a survey was conducted in three provinces to understand current planting sites and production of planted trees. The results indicated that J. regia was planted personally in gardens of local people in Lai Chau, Lao Cai and Ha Giang provinces, sharing borderlines with China. The planted trees are 10-30 years old with some exceptions of up to 40-50 years old. Generally, each household owns 2-3 fruited trees with some exceptions of up to 10 trees. After planting 7 years, trees fruit annually. However, the production varies among trees. A best 20-25-year-old tree can yield 55 kg fruits/year with current market price of 1.5 US$/ 1 kg fruits. There exists high variation of fruit production among planted sites, as results of climate difference, and unknown source and sexual propagation seedlings. It is concluded that to establish an extensive plantation of J. regia for high fruit production, selecting superior genotypes from local populations should be conducted, then vegetative propagation such as grafting should be applied to produce good and uniform seedlings.