The role of microscopic plasma instabilities in the current sheet in the violation of the ideal magnetohydrodynamic (MHD) condition is investigated by means of a $2\frac{1}{2}$-dimensional explicit particle simulation code. Two instabilities, lower hybrid drift instabilities (LHDIs) and drift kink instabilities (DKIs) are found to evolve in the current sheet. In the LHDI growing phase, nonlinear coupling of the fluctuations of the electric field and particle density generates the outward flow and deforms the current sheet profile. The DC electric field leading to the magnetic flux reduction and the damping of equilibrium current are observed in the DKI growing phase. The force balance between the averaged electric force term and the additional wavy component associated with the fluctuations of magnetic field and current density holds at the neutral sheet. This suggests that the DKI can contribute to creating anomalous resistivity and triggering the collisionless magnetic reconnection.