Quantum dot cellular automata (QCA) is considered one of the most promising technologies to replace the current CMOS technology. Compared with the traditional transistor technology, the computation relies on a new paradigm based on the interaction between nearby QCA cells. It has significant advantages, such as operating frequency (THz), high device density, and low power consumption. In this brief, a novel XOR/XNOR-function logic gate with two inputs, two enable inputs and one output is proposed and designed in Quantum-dot Cellular Automata (QCA) nanotechnology. In order to demonstrate the functionality and capabilities of the proposed QCA-based XOR/XNOR architecture, performance is evaluated and analyzed. The proposed XOR/XNOR logic gate has a superb performance in terms of area, complexity, power consumption and cost function in comparison to some existing QCA-based XOR architectures. Moreover, some efficient circuits based on the proposed XOR/XNOR gate are designed in QCA.