The invention discloses an organic composite efficient sulfur removal agent for oil-gas field and preparation method and application of the organic composite efficient sulfur removal agent. The sulfur removal agent is characterized in that water serves a solvent and comprises an alcohol amine component A, an alcohol amine component B, a triazine derivative, inhibiter, synergist and low-molecular mass alcohols; the alcohol amine component A refers to methyldiethanolamine, the alcohol amine component B refers to one of triethanolamine and diethanolamine or a mixture of triethanolamine and diethanolamine; triazine derivative refers to hexahydro-1,3,5-tris-s-triazine; the inhibiter refers to seventeen alkenyl amide ethyl imidazoline; the synergist refers to sulfolane; the low-molecular mass alcohols refer to one of ethylene glycol and glycerol or a mixture of ethylene glycol and glycerol. The sulfur removal agent has the advantages of good selectivity on sulfuretted hydrogen, small dosage, quick effect, high sulfur removal efficiency, no corrosion of steel, stable product performance, difficulty in heating decomposition, capability of being biodegradable and the like; sulfide like sulfuretted hydrogen existing in extraction of an oil-gas well can be effectively removed or reduced to safety threshold value range in content, corrosion of sulfide on pipelines and equipment is inhibited, and safety on the equipment and operation personnel is guaranteed.