The purpose of this study was to clearly understand the health-promoting potentials of broccoli seeds and sprouts according to identify their representative bioactive compounds and antioxidant activities in six varieties. Sulforaphane (SF) extraction was firstly optimized from seeds and sprouts. Then SF extracted under optimized conditions from seeds and sprouts were compared. Most varieties obtained the maximum SF, total phenolic (TP) and flavonoid (TF) contents in sprouts on day 3. SF contents in sprouts were 46%–97% of seeds, whereas TP and TF contents in sprouts were 1.12–3.58 times higher than seeds among varieties. After in vitro digestion, broccoli sprouts from MNL variety kept considerable SF, TF, and TP contents, as well as antioxidant capacities, with all values higher than seeds. Compared with seeds, sprouts after 3 days germination were also recommended as raw materials of functional foods that possess high health-promoting potential.