NOVELTY - A copper titanium dioxide nuclear-shell nanoparticle preparing method involves controlling proportions of tetrabutyl titanate and polyethylene glycol, and mixing solvent with the proportion controlled raw materials to obtain copper-titanium dioxide composite nano-powder with a nuclear shell structure. The obtained product is reacted in a blowing drying box for 10-24 hours at 150-200 degrees C followed by centrifuging for 10-30 minutes at 4000-12000 rpm, dispersing in 100 ml of absolute ethanol, and drying for 24 hours at 50 degrees C to obtain copper titanium dioxide nuclear-shell nanoparticle.    USE - Method for preparing copper titanium dioxide nuclear-shell nanoparticle that is utilized as electrode material and photocatalyst material of a dye sensitized solar cell.    ADVANTAGE - The method enables preparing the copper titanium dioxide nuclear-shell nanoparticle in a simple, environment-friendly and inexpensive manner.    DETAILED DESCRIPTION - A copper titanium dioxide nuclear-shell nanoparticle preparing method involves controlling proportions of cuprous chloride, ammonia water, ascorbic acid, tetrabutyl titanate, sodium citrate, urea and polyethylene glycol, and mixing solvent with the proportion controlled raw materials to obtain copper-titanium dioxide composite nano-powder with a nuclear shell structure. The cuprous chloride is dissolved into ammonia water solvent to obtain cuprous chloride ammonia water solution followed by providing to a beaker to stir for 15 minutes, and dissolving polyethylene glycol to de-ionized water to obtain polyethylene glycol solution. The sodium citrate is dissolved in the de-ionized water to obtain sodium citrate solution. The ascorbic acid is dissolved in the de-ionized water to obtain ascorbic acid solution. The tetrabutyl titanate is dissolved in absolute ethanol to obtain tetrabutyl titanate ethanol solution followed by adding 0.001-0.01 mole of urea to the tetrabutyl titanate ethanol solution, stirring for 30 minutes, and supplying the mixed solvent to a reaction device with PTFE liner and a stainless steel kettle. The obtained product is reacted in a blowing drying box for 10-24 hours at 150-200 degrees C followed by centrifuging for 10-30 minutes at 4000-12000 rpm, dispersing in 100 ml of absolute ethanol, and drying for 24 hours at 50 degrees C to obtain copper titanium dioxide nuclear-shell nanoparticle.