We perform first-principles calculations to study the energetics and electronic properties of silicene and MoSe2 heterobilayers (Si@MoSe2 HBLs). It is found that the silicene is bound to MoSe2 substrate with a binding energy of -0.56 eV per silicon atom, indicating a weak interaction between two layers. The nearly linear band dispersion character of silicene with a sizable band gap is obtained in Si@MoSe2, due to the variation of on-site energy induced by MoSe2 substrate. Remarkably, the band gaps and electron effective mass (EEM) of HBLs can effectively be tuned by interlayer spacing, external electric field, and strains. These findings indicate that Si@MoSe2 HBLs are promising candidates for high-performance silicene-based FET channel operating at room temperature, in which both finite band gap and high carrier mobility are obtained. (C) 2015 Elsevier B.V. All rights reserved.