The invention provides a preparation method of an 
iminodiacetic acid functionalized magnetic adsorption material, which comprises the following steps: weighing 
ferric chloride, dissolving the 
ferric chloride in 
ethylene glycol, after complete dissolving, adding 
sodium acetate, carrying out ultrasonic treatment, carrying out heating reaction to obtain a 
solid product, and conducting washing and 
drying to obtain magnetic Fe3O4 
powder; adding absolute ethyl 
alcohol and deionized water into the magnetic Fe3O4 
powder, conducting ultrasonical dispersing, adding concentrated 
ammonia water, then adding 
tetraethyl orthosilicate, repeatedly adding 
tetraethyl orthosilicate for multiple times, and conducting reacting at 
room temperature to obtain a Fe3O4-coated SiO2 material; dispersing the Fe3O4-coated SiO2 material into absolute ethyl 
alcohol, adding concentrated 
ammonia water and 3-aminopropyl 
triethoxysilane, and conducting reacting at 
room temperature to obtain aminated magnetic beads; and weighing 
sodium chloroacetate, dissolving the 
sodium chloroacetate in deionized water and absolute ethyl 
alcohol to obtain an 
ethanol solution of 
sodium chloroacetate, adding aminated magnetic beads into the 
ethanol solution of 
sodium chloroacetate, adding an acid-binding agent, and carrying out a heating reaction to obtain the 
iminodiacetic acid functionalized magnetic adsorption material. The adsorption material provided by the invention is good in adsorbing effect.