<p>A decellularized extracellular matrix (dECM) constitutes a pivotal biomaterial created by decellularizing the natural extracellular matrix (ECM). This material serves as a supportive medium for intricate cellular interactions, fostering cell growth, differentiation, and organization. However, challenges persist in decellularization, necessitating a balance between preserving the ECM structural integrity and achieving effective cellular removal. An approach to enhancing decellularization involves pre-eliminating unnecessary tissues and effectively reducing final DNA levels to lower than 50 ng/mg ECM on preprocessed tissues. Although this strategic step augments decellularization efficiency, the current manual execution method depends on the operator’s skill. To address this limitation, this study proposed an automated raw tissue slicing system that does not require tissue preparation for slicing. Through carefully controlled tissue applanation pressure and oscillatory incisions with optimized parameters, the system achieved a precision within ±10 µm in obtaining submillimeter-scale tissue slices of the porcine cornea while avoiding significant microscopic complications in the tissue structure, as observed by tissue histology. These findings suggested the system’s capability to streamline and automate preliminary tissue slicing operations. The efficacy of this approach for decellularization was validated by processing porcine corneas using the proposed system and subsequently decellularizing the processed tissues. DNA level analysis revealed that sliced, subdivided tissues created by this system could expedite DNA reduction even at the initial steps of decellularization, enhancing the overall decellularization procedure.</p>