The invention relates to the technical field of urea formaldehyde resin preparation. A urea resin preparation reaction kettle comprises a stirrer and a container, wherein a feeding hole is formed in the container; a reversing tube is hinged to the feeding hole in a spherical surface matching sealing manner; the container is provided with shock insulation feet and lifting lugs which are connected through mounting bolts together with screw nuts; the screw nuts comprise main body sections and swinging stop sections; large-diameter sections are arranged at the outer ends of the main body sections; swinging grooves are formed in the large-diameter sections; swinging heads are arranged at the swinging stop sections; the swinging stop sections are arranged inside the large-diameter sections in a rotational penetration manner; the swinging heads are inserted into the swinging grooves; swinging gaps are formed between the swinging heads and the swinging grooves; threads of the main body sections and threads of the swinging stop sections can be adjusted to on the same spiral line. The preparation method of the urea formaldehyde resin adopts melamine, paraformaldehyde and urea as raw materials, and thus the problems that a great deal of wastewater can be generated and severe pollution can be caused when the urea formaldehyde resin is prepared can be solved. The reaction kettle provided by the invention has the advantages of being convenient to hoist, large in reversing range and good in shock insulation effect, and the problems that a conventional reaction kettle is inconvenient in feeding hole reversion, inconvenient to hoist and poor in shock insulation effect can be solved.