Forty varieties of asparagus bean Vigna unquiculata W.ssp. sesquipedalis (L.) Verd were studied in three years in vegetable farm in the University, to test the effects of varieties of asparagus bean on the population of Maruca testulalis Geyer. The results in the experiments showed that the densities of the larvae of the insect pest in the flowers and in the beans were different significantly between the varieties of the bean. The larval densities of variety Xinqing were 18, 17.3 and 6.33 larvae in 30 flowers of the bean in 1988, 1989 and 1990 respectively, and lower than other varieties. It was found that the larval population between the stages in flowers and in beans showed a positive regression corelationship.