Industrial scale NH3 production is mainly produced by the Haber Bosch process, but it suffers from intensive energy consumption with serious CO2 emission. Electrochemical N2 reduction reaction (NRR) is now used for energy-saving NH3 synthesis, which needs highly efficient electrocatalysts for N2 activation. In this work, we have computationally studied what are main factors for affecting N2 molecule activation and NRR process on VO2c decorated TiO2 (101) surface by changing its structures or electronic features. Furthermore, a promising NRR electrocatalyst is successfully predicted.