The hydrogenation of carbonyl group of cinnamaldehyde (CALD) yields a desired product, which is cinnamyl alcohol (CALC), along with a couple byproducts, which are hydrocinnamaldehyde (HCALD) and hydrocinnamyl alcohol (HCALC). Recently, metal-organic frameworks (MOFs) are shown to be a new kind of porous material that has great potential in catalysis due to their large surface area and high porosity. In this project, small platinum (Pt) nanoparticles encaged in metal-organic-framework (MOF), particularly UiO-66, were prepared to achieve the selective hydrogenation of cinnamaldehyde. The amine-functionalized MOF (UiO-66-NH2) was found to be able to achieve much higher Pt loading than the pristine, UiO-66, thus leads to higher conversion of cinnamaldehyde. However, the amine-functionalized could reduce the stability of the original metal-organic framework UiO-66. In addition, we noted that the higher Pt loading is preferred because increasing the amount of catalyst will increase both the conversion of cinnamaldehyde and the selectivity to desired product. Other important factors, such as solvents and reaction time were also investigated.