Menispermaceae is represented by about 70 genera and approximately 520 species. In Vietnam, it is represented by 19 genera, 50 species and two varieties, of which six species are endemic. Most species are dioecious climbers, rarely trees, shrubs, or herbs and distributed in tropical region, sometimes subtropical regions and warm temperate zones. | HỘI NGHỊ KHOA HỌC TOÀN QUỐC VỀ SINH THÁI VÀ TÀI NGUYÊN SINH VẬT LẦN THỨ 6 MORPHOLOGICAL CHARACTERISTICS AND KEY TO GENERA OF FAMILY MENISPERMACEAE IN VIETNAM VU TIEN CHINH, BUI HONG QUANG Institute of Ecology and Biological Resources, Vietnam Academy of Science and Technology TRAN THI PHUONG ANH Vietnam National Museum Nature, Vietnam Academy of Science and Technology Menispermaceae is represented by about 70 genera and approximately 520 species. In Vietnam, it is represented by 19 genera, 50 species and two varieties, of which six species are endemic. Most species are dioecious climbers, rarely trees, shrubs, or herbs and distributed in tropical region, sometimes subtropical regions and warm temperate zones. I. MATERIALS AND METHODS This study of family Menispermaceae from Vietnam was based on field observations, laboratory and library work. II. RESULTS AND DISCUSSION Large woody vines (Fig. 1): They are usually 10 - 40 m long, and about - 5 cm in diameter. Tinomiscium, Albertisia, Lamicia, Pycnarrhena, Pachygone, Coscinium, Anamirta, Arcangelisia, Fibraurea, Diploclisia, Hypserpa (Fig. 1).Small woody vines: 5 - 8 m, Parabaena, Tiliacora, Tinospora. Herbaceous vines: 1 - 4 m, Cyclea, Cissampelos, Cucculus, Pericampylus (Fig 1d). (Fig. 1b). Stephania is the only genus of the family having tuberous rootstock. Leaves (Fig. 2): Stipules usually absent; Petiole often with proximal and distal pulvinus. Petiole vascular bundle transection annular. Leaf venation is usually palmatinerved, but few genera have pinnate venation. Leaves are typically more or less subpeltate, with the insertion of the petiole being scarcely in from the margin of the lamina, but few taxa have peltate leaves. Inflorescence: The inflorescences of Menispermaceae are usually determinate, axillary or borne on defoliate branches (ramiflorous) or old wood (cauliflorous), rarely terminal, solitary or fasciculate; most often in racemes, cymes, or thyrses, sometimes in panicles or cymose .