In order to obtain industrial gas flow, the low-permeability sandstone conglomerate gas reservoir requires reservoir reconstruction. Young's modulus, Poisson's ratio, horizontal principal stress and brittleness index are the basic parameters to simulate and optimize the efficient the reconstruction of sandstone conglomerate gas reservoir. In view of the significant horizontal and longitudinal variations in lithology and physical property parameters of offshore sandstone conglomerate reservoir, and the challenges in accurately characterizing rock mechanics and in-situ stress parameters, this paper focuses on the development horizon of offshore low-permeability sandstone conglomerate gas reservoir. Based on core experimental data, rock mechanics parameter calibration is performed, leading to the development of an interpretation model that correlates rock mechanics parameters with acoustic wave and density logging parameters. This model facilitates the interchange of dynamic and static parameters to calculate the elastic parameters. Utilizing elastic wave theory in conjunction with conventional logging data, rock mechanics parameters such as Poisson's ratio, elastic modulus and geostress field are established on a three-dimensional geological model. This provides a necessary basis for the evaluation of fracturing property and the simulation of fine fracture morphology in offshore lowpermeability sandstone conglomerate reservoirs.