The covalent excited states and ground state of the Br-2 molecule has been investigated by using four-component relativistic COSCI and MRCISD methods. These methods were performed for all covalent states in the representation Omega((+/-)). Calculated potential energy curves (PECs) were obtained at the four-component COSCI level, and spectroscopic constants (R-e, D-e, D-0, omega(e), omega X-e(e), omega(e)y(e), B-e, alpha(e), gamma(e), T-e, D-v) for bounded states are reported. The vertical excitations for all covalent states are reported at COSCI, MRCISD, and MRCISD+Q levels. We also present spectroscopic constants for two weakly bounded states (A': (1)2(u) and B':(1)0(u)(-)) not yet reported in the literature, as well as accurate analytical curves for all five relativistic molecular bounded sates [the ground state X:0(g)(+) and the excited states A:(1)1(u), B:(1)0(u)(+), C: (2)1(u), and B':(1)0(u)(-)] found in this work.