Abstract: With plane wave vectors and pseudopotential method within the fbme of density functional theory.we study band structure,Fermi surfaces and density of state of BaTi₂As₂O.It is found that BaTi₂As₂O is a nonmagnetic metal and density of state at Fermi level is dominated by Ti 3d electrons.Ti 3d orbitals are hybridized with As 4p orbitals strongly rather than O 2p orbitals.A magnetic ground state of BaTi₂As₂O is not found,which is consistent with a study on Na₂Ti₂Sb₂O by Pickett.