This paper deals with Direction of Arrival (DOA) Estimation using Uniform linear array (ULA) for the case of more sources than sensors in the array processing. Khatri-Rao subspace approach, introduced for DOA estimation for this, in non-stationary signal model. The technique will be shown to be capable to handle stationary signals, too. Identifiability conditions of this approach are addressed. The Cramer-Rao Bound (CRB) is derived for the superior setting and the statistical performance of the estimation method is compared with CRB. Simulations show that the mean-squared error performance of Khatri-Rao approach is within 3 dB of the CRB.