Unconventional tight reservoirs are characterized by strong non-homogeneity, low resource abundance, low porosity and low permeability. Compared with onshore unconventional reservoirs, hydraulic fracturing of offshore tight gas reservoirs has greater safety risks greater and more operational difficulties, leading to greater difficulty in balanced reservoir modification. Therefore, deployment of horizontal wells for hydraulic fracturing development in offshore tight gas reservoirs requires precise evaluation of reservoir geomechanical characteristics, analysis of the fracturability of horizontal well sections, and fracturing of well sections with similar geomechanics, which can support precise, balanced and efficient development of offshore gas reservoirs. Taking a tight gas reservoir in offshore as the research object, in this study, an engineering fracturability analysis method based on brittleness and in-situ stress difference was proposed, and an engineering sweet spot prediction model was established by kernel density estimation method to estimate the probability density function and cumulative probability function of engineering fracturability. Based on the engineering sweet spot prediction, hydraulic fracturing segments were optimized to achieve a differentiated design of segment spacing. Based on the concept of integrated geological and engineering, hydraulic fracturing simulation and production prediction were carried out in this study. The simulation results verified the feasibility of hydraulic fracturing and the reliability of engineering sweet spot prediction in target reservoir, which provides a significant technical support for the optimization of horizontal well fracturing scheme and large-scale beneficial development of offshore tight gas reservoirs.