Previous research implicated that feeling-of-knowing (FOK) and feeling-of-not-knowing (FOnK) might be two different cognitive processes. Based on this hypothesis, an experiment was conducted by examining FOK and FOnK judgment under different levels of processing and different kinds of materials. The results showed that processing depth had positive effects on FOK judgment, but little effects on FOnK judgment, conversely, it even decreased the accuracy of FOnK judgment, which demonstrated that FOK judgment and FOnK judgment were two different cognitional processes. Implications and limitations are discussed.