Both quantum and DNA computing approaches can be used to accomplish operations at a very high speed and efficiency. There is a critical issue that occurs when merging both computing systems for a single activity. Quantum computers are a million times quicker than the world’s fastest supercomputer. As a result, quantum operations produce instantaneous results. However, DNA procedures take a long time to prepare for its operations. So, the quantum computer’s output qubits cannot be instantly inserted into the DNA system. Thus, when working with the Quantum-DNA system, a temporary storage device or system is required where the qubits may be held for a very short time. So, a Quantum Cache memory is needed to store qubits during a Quantum-DNA computing circuit operation. The structure and working procedure of quantum and DNA cache memory are described in this chapter. In the DNA-Quantum circuit operation, a DNA cache memory is needed to store DNA sequences for temporary purposes.