Correlation is investigated between supercooled liquid regions (SLRs) △Tx (=Tx 2 Tg, where Tx is the onset crystallization temperature and Tg the glass transition temperature) of ferrous bulk metallic glasses (BMGs) and three bond parameters, i.e. electronegativity, atomic size and valent electron. From the available experimental data in literatures, △Tx has strong correlation with the bond parameters. A semiempirical equation is established to elucidate the correlation between DTx and the three bond parameters. In detail, △Tx increases obviously with the increase of the atomic size parameter (δ), and electronegativity difference(△x) and the electron concentration. An ellipse arc with thickness derived from the equation is drawn to determine the range of BMG with large SLR.