Abstract: The present invention relates to the unbalanced multi-block styrene-butadiene-styrene (SBS) and provides the copolymer represented by the following structure, mB1*S1-lB2-S2-sB3, wherein B is a butadiene block, S is a styrene block, l, m, s are the relative size among the blocks (i.e., large size, middle size, and small size, respectively), and * is the tapered block between mB1 block and S1 block (i.e., random copolymer of a kind). They have to satisfy the following related expressions. 0.01lB2?mB1?0.5lB2 and 0.01mB1?sB3?0.5mB1 ??a) 0.5S1?S2?1.5S1 ??b) 5%?*%?25% ??c) In the related expression, the value of B1 and S1 include tapered block for the sake of convenience, and * % is the random styrene content in all the styrene in SBS. The unbalanced multi-block SBS of this invention exhibits excellent processability in the preparation of hot-melt adhesives, reducing processing hours.