This study was conducted to investigate on effects of seedling culture test on nursery soil mixed with the wasted mushroom media(WMM), the by-product of Agaricus bisporus media which was manufactured through secondary composting and sterilization process. The results are as follows; 1) the physico-chemical and biological properties of WMM were adequate in accordance with the nursery soil management regulations. 2) In the rice seedling culture test, a leaf growth factor at treatments mixed with WMM 40～80% was more favorable about 7～11% than the result of some market products. 3) In the seedling culture test of horticultural crops, the growths of chinese cabbage, cucumber, and red pepper were superior at the WMM 20%, 10%, and 5% treatment, respectively. Therefore, the wasted mushroom media on nursery soil should be recognize as applying and utilizing effects for rice and horticultural crops seedling culture.