The invention discloses a preparation method and an application of a multi-walled carbon nanotube supported La and Al co-modified platinum-based catalyst. A multi-walled carbon nanotube is subjected to acid modification, a certain amount of chloroplatinic acid water solution is added, a nitrate precursor is added according to a certain proportion, and drying, calcining and reducing are performed after reaction to obtain the catalyst, namely, La-Al-Pt/MWCNT. The preparation method is simple, the needed catalyst can be obtained by a primary impregnation method, a carrier is low in price and easyto obtain, the cost is greatly reduced, recycling effects are good, the obtained catalyst is used for glycerol hydrogenation reaction, short in reaction time, economical, effective, environmentally friendly and low in hydrogen consumption, products are easily separated, high glycerol transformation rate and 1, 3-propylene glycol selectivity can be achieved under mild reaction conditions, processproduction conditions are improved, and the quality of corresponding products is improved.