NOVELTY - Microemulsion comprises (in wt.%): methylamino abamectin benzoate (0.5-10), solvent (5-20), cosolvent (1-15), emulsifying agent (5-40), stabilizing agent (0.1-3) and water.    USE - The microemulsion is used as agricultural insecticide.    ADVANTAGE - The microemulsion is environmentally-friendly, reduces the use of aromatic organic solvent and has improved potency and utilization rate of insecticide.    DETAILED DESCRIPTION - Microemulsion comprises (in wt.%): (0.5-10) methylamino abamectin benzoate, (5-20) solvent, (1-15) cosolvent, (5-40) emulsifying agent, (0.1-3) stabilizing agent and water. The solvent is aromatic hydrocarbon solvent chosen from benzene, methylbenzene, dimethylbenzene, ethylbenzene and acetone. The solvent is ester solvent chosen from methyl formate, ethyl formate, propyl formate, butyl formate, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl propionate, ethyl propionate, butyl propionate, methyl butyrate, ethyl butyrate and butyl butyrate. The cosolvent is alcohol chosen from methanol, ethanol, propyl alcohol, isopropanol, butanol, isobutanol, glycol, propylene glycol and their combinations. The emulsifying agent is anionic surface active agent or non-ionic surface active agent. The anionic surface active agent is dodecyl sodium bensosulfonate. The non-ionic surface active agent is chosen from alkylphenol ethoxylates, benzylphenol ethoxylates, styrene phenol ethoxylates, tristyrylphenol polyoxyethylene ether and polyacrylamide. The stabilizing agent is chosen from urea, polyvinyl alcohol and polyacrylamide. An INDEPENDENT CLAIM is included for method for preparing the above-cited microemulsion, which involves mixing solvent, cosolvent and methylamino abamectin benzoate uniformly at rotating speed of 40-100 revolutions per minute (rpm), adding emulsifying agent and stabilizing agent to the mixture and adding water (100%) to the mixture and continuously stirring the mixture for 1-2 hours to obtain transparent solution.