The Invention provides a TRAIL cell-penetrating peptide (CPPs)-like mutant MuR6 and a preparation method and the application thereof. The amino acid sequence of the mutant is SEQ ID NO: 2. The mutant selectively transforms the amino acid coding sequence of No. 114-119 of the outer fragment of the TRAIL wild-type protein cell membrane from VRERGP to RRRRRR, i.e., mutates valine into arginine on the 114 th coding sequence, glutamic acid into arginine on the 116 th coding sequence, glycine into arginine on the 118 th coding sequence and proline into arginine on the 119 th coding sequence, turning the coding sequence of N-terminal of the mutant protein into that of six arginines and making it a protein containing CPPs-like structure. Having a superior therapeutic effect on different types of tumor, the TRAIL mutant is a new generation of high-efficient drug for inducing tumor apoptosis of much potential.