A new pregnane glycoside, named (20R)-O-(3)-${eta}$-D-glucopyranosyl-($1{ ightarrow}2$)-${alpha}$-L-arabinopyranosyl-pregn-5-en-$3{eta}$,20-diol (1), and seven known compounds, brusatol (2), bruceine B (3), bruceine D (4), yadanziolide A (5), bruceine E (6), yadanzioside G (7), and yadanzioside B (8), were isolated from the cultivated dry seeds of Brucea javanica. The structure of 1 was elucidated on the basis of 1D- and 2D-NMR spectroscopic analyses. Their inhibitory effects on tumor cells were also tested. Compound 1 was slightly active against HL-60, SMMC-7721, A-549, and MCF-7 tumor cells. Compounds 2 and 3 demonstrated significant inhibitory activities against all tested cells. These results indicate that cultivated B. javanica could replace the wild plant as an antitumor plant resource.