In order to investigate the variations on the ratio of mannose to galactose in the seeds of Phaseolus angularis, 17 local strains (Yangyang, Pyeongchang, Ganghwa, Pocheon, Geumsan, Seocheon, Jincheon, Danyang, Tongyeong, Sancheong, Gumneung, Wolseong, Wando, Gokseong, Okgu, Jangsu, Bukjeju), which are located from $33^{\circ}15'N$ to $38^{\circ}11'N$, were selected according to their latitudes and geographical distances. The seeds of these strains were collected and their contents of mannose and galactose were analyzed. Mannose contents in the seeds were variable, ranging from 17.071 mg/g at its highest (Jangsu) and 6.488 mg/g at its lowest (Geumsan). The contents of galactose also showed remarkable differences, ranging from 9.477 mg/g (Wolseong) to 19.877 mg/g (Jangsu). The local strains were classified into 3 variation types - coastal type I (Wando, Okgu, Bukjeju), the inland type (Jangsu, Weolseong, Danyang, Geumneung, Pyeongchang, Sancheong) and coastal type II (Ganghwa, Seocheon, Tongyeong, Jincheon), as well as 4 strange strains (Gokseong, Yangyang, Pocheon, Geumsan) according to the geographical climatic type and the ratio of mannose to galactose, which indicate the hardness of seeds in Leguminosae and ranged from 0.64 to 1.22. The variation types are very significant genecologically as evidence for microevolution related to natural and artificial selection in cultivated plants.