The synthesis and properties of asymmetric KNbO3/KTaO3 superlattices is examined. Interdigitated electrodes are fabricated for temperature-dependent capacitance measurements. The nonlinear dielectric response of 1/N superlattice exhibits the anomalous positive tunability behavior indicative of antiferroelectricity. In contrast, the N/1 KNbO3/KTaO3 structures (N≫1) appear to be either ferroelectric or paraelectric, depending on the temperature. Discussion of possible mechanisms for this behavior is given.