The invention belongs to the technical fields of gas purification and environment protection, and specifically relates to a solid adsorbent for removing H2S, CO2, CS2, COS, organic sulfur (mercaptan, etc.), and the like from mixed gas. The solid adsorbent is composed of a porous solid carrier and a loaded object. The porous solid carrier comprises active carbon, molecular sieve, silica gel, alumina, hydrotalcite, derivatives of hydrotalcite, and metal organic framework compounds (MOFs). The loaded object is composed of a main agent and an auxiliary agent. The loaded object accounts for 10 to 75 wt% of the weight of the porous solid carrier. The main agent accounts for 30 to 80% of the weight of the loaded object. The provided solid adsorbent is used to remove sulfur and carbon, can be used in reactors such as fixed bed reactor, moving bed reactor, and the like, can be used at a low temperature, and has the characteristics of adjustable selectivity, quick adsorption speed, large adsorption capacity, high removing rate of COS, CS2, and organic sulfur (mercaptan, etc.), and low energy consumption of regeneration.