This experiment compared and analyzed the Oriental and Western flower arrangement programs to examine the effect of horticultural therapy program on mental symptoms of schizophrenics. This study respectively executed the Oriental and Western flower arrangement to 20 men and women patients of schizophrenia and bipolar who have been treated for their rehabilitation in the Daegu Rehabilitation Center at Sindang-dong, Dalso-gu, Daegu Metropolitan City by 12 times program from April 16, 2002 to July 23, 2002. this study investigated and tested the effectiveness by SCL-90-R and Self-Esteem Scale with diagnosing them by horticultural therapy evaluation table (KHY type) after having enforced each program. This study made them choose their favorite color whenever executing each program, and investigated their preference of flower color. In result of SCL-90-R on the Oriental arrangement, they showed their mental symptom to be worsen after the execution than before the execution of the program, but there wasn't any significant difference. However in the case of the Western flower arrangement their mental symptom appeared to be improved. In result of Self-Esteem Scale, it appeared to be higher in all of the Oriental and Western flower arrangement after the execution than before the execution of horticultural therapy program, but there wasn't ant significant difference. On the horticultural therapy evaluation table, they showed a significant development(p=0.05) in emotional improvement and social improvement by all the Oriental and Western flower arrangement , Especially the improvement of the Western flower arrangement appeared to be higher in emotional improvement such as activity, integration control, independence, and solitary than the Oriental flower arrangement (p=0.01). The improvement of the Western flower arrangement appeared to be higher also in social improvement such as sociality, cooperativeness, and participation than the Oriental flower arrangement (p=0.01). In result of investigating their preference of flower color, they appeared to prefer the generally bright and clear colors in the order of red, dark pastel , yellow, white, violet, and light pastel through the Oriental and Western flower arrangement, In the above result of consideration, the Oriental and Western flower arrangement had the effect to restoration of emotion and sociality of schizophrenics, but the Western flower arrangement on is considered to be more desirable as flower arrangement for schizophrenics than the Oriental flower arrangement.