Abstract: Fourteen constituents were isolated from the roots of Salvia miltiorrhiza f. alba. Two of them were new compounds and were named 1, 2, 15, 16-tetrahydrotanshiquinone (Ⅰ) and tanshinaldehyde (Ⅱ). The others were identified as Ro-090680 (Ⅲ), dihydroisotanshone Ⅰ(Ⅳ), danshexinkun B(Ⅴ), miltirone (Ⅵ), nortanshinone (Ⅶ), hydroxytanshinone Ⅱ-A(Ⅷ), tanshinone Ⅰ(Ⅸ), dihydrotanshinone Ⅰ(Ⅹ), tanshinone Ⅱ-A(ⅩⅠ), cryptotanshinone (ⅩⅡ), methylenetanshiquinone (ⅩⅢ), methyltanshinonate (ⅩⅣ), Ⅰ and Ⅲ showed inhibitory activity against P₃₈₈ Leukemia cell in vitro. Ⅲ was reported to be a potent inhibitor of rabbit platelet aggregation induced by collagen.