In view of the high computational complexity of traditional linear equalization algorithms in Orthogonal Time Frequency Space (OTFS) systems, a minimum mean square error (MMSE) channel equalization algorithm based on Matrix Chunking Lower and Upper Triangular Decomposition (CLU) is proposed. The proposed algorithm derives the structural properties of the chunked MMSE equalization matrix by leveraging the block diagonal structure of the Cyclic Prefix OTFS (CP-OTFS) time-domain channel matrix and the quasi-band structure of its constituent block matrices. On this basis, triangular decomposition combined with forward and backward substitution is used to avoid matrix inversion. This approach significantly reduces the complexity of the MMSE algorithm without sacrificing its performance.