A facile route to synthesize a new type of multifunctional nanocomposites is reported. Here

PDMAEMA (poly[2-(dimethylamino)ethyl] methacrylate) is a key macromolecule serving as a bridge between magnetic Fe

2

O

3

nanoparticles and luminescent quantum dots. Both Fe

2

O

3

nanoparticles and II-VI semiconductor quantum dots with a narrow size distribution are synthesized through a two-phase thermal approach. Subsequently

the atom transfer radical polymerization (ATRP) technique was applied to prepare magnetic Fe

2

O

3

@PDMAEMA core-shell nanoparticles. The thickness of PDMAEMA shell can be easily controlled by adjusting the reaction time. Finally

the ligand exchange method was exploited to modify II-VI quantum dot with amine-containing polymer of PDMAEMA

which led to quantum dot securely bound by Fe

2

O

3

@PDMAEMA core-shell nanoparticle to form a multifunctional nanocomposite. The resulting nanocomposite remains variable emission by tuning the II-VI semiconductor type and particle size and shows

H

c

at 49 kA/m and

T

b

at 16 K from Fe

2

O

3

nanoparticles. The self-assembled behavior for the resulting samples is also discussed.