“…Recently, Sadeghieh et al in [1] derived Hosoya polynomial of some cactus chain and studied some degree based topological indices. we refer the reader [2][3][4][5] for further study about cactus graph. In this work, we study the mathematical property of general Zagreb index or (a, b)-Zagreb index of some general ortho and para cactus chains and hence consider their special cases such as triangular chain cactus T n , ortho chain square cactus O n and para-chain square cactus Q n , where n denote the length of the chain and then we derive some explicit expressions of the same for other degree based topological indices such as Zagreb indices, forgotten index, redefined Zagreb index, general first Zagreb index, general Randić index, symmetric division index for particular values of a and b of general Zagreb index.…”