In this study, we discuss the electrical properties of junctions consisting of metal electrodes and Nb-doped SrTi O3 (001) single crystals. The junctions formed with large work function metals (Ni, Au, Pd, and Pt) resulted in rectifying transport. A hysteretic feature was observed in the current (I) -voltage (V) and capacitance (C) -V characteristics of these junctions upon polarity reversal. The ideal Schottky-Mott rule could not explain the barrier height obtained from the I-V data, indicating the existence of interface states. Analyses of the C-V data revealed that a low dielectric constant layer existed at the interface. The interface states and layers affected the transport and the related resistance switching characteristics of the junctions.