Corrosion inhibitor for oil well and preparation method thereof

The invention relates to a corrosion inhibitor for an oil well, which is used for inhibiting corrosion to a device caused by a corrosion medium during the oilfield oil production process, and an N-alkylamino-2-perfluoroalkyl imidazoline quaternary ammonium salt compound is taken as a main agent. The corrosion inhibitor for the oil well comprises the following components by weight percent: 5-15% of N-alkylamino-2-perfluoroalkyl imidazoline quaternary ammonium salt, 0-5% of hydrocarbon imidazoline and derivatives thereof, 10-20% of trolamine, 0-5% of urea and 55-85% of solvent. When in preparation, the raw materials are sequentially added into a reaction kettle and stirred for 10-30min at the temperature of 40-80 DEG C, and then a finished product is prepared. The product has excellent metal corrosion inhibition performance in corrosion resistance of the oil well in an oilfield and can effectively ease the metal corrosion problem to oil well production, pipeline transportation and oil product processing caused by various corrosion media.