The invention discloses a 
porous carbon-loaded 
composite material catalyst as well as a preparation method and application thereof. The catalyst consists of a carrier, an 
active component and a carbon 
quantum dot, wherein the 
active component and the carbon 
quantum dot are loaded on the carrier; the size of the carbon 
quantum dot is not more than 10 nm; the carrier is porous 
activated carbon; the 
active component is one of or a combination of several of 
platinum, 
palladium, 
iridium, 
ruthenium and 
rhodium; based on the 
mass of the carrier, the loading quantity of various metals in the active component is shown as follows: the 
platinum is 0-10.0 percent by weight, the 
palladium is 0-10.0 percent by weight, the 
iridium is 0-10.0 percent by weight, the 
ruthenium is 0-10.0 percent by weight, and the 
rhodium is 0-5.0 percent by weight; the loading quantity of the 
platinum, the 
rhodium and the 
palladium is not 0; the total loading quantity of the active component is more than 0.5 percent by weight and is not more than 20 percent by weight; based on the 
mass of the carrier, the loading quantity of the carbon 
quantum dot is not more than 15.0 percent by weight. The invention further provides application of the 
porous carbon-loaded 
composite material catalyst to the reaction of synthesis of chloroaniline by selective 
catalytic hydrogenation of chloro-
nitrobenzene. The catalyst has the characteristics of being high in conversion rate, high in catalytic activity and high in stability.