NOVELTY - Preparing catalyst comprises e.g. adding carbon nanotubes into concentrated sulfuric acid and concentrated nitric acid, stirring uniformly, where stirring temperature is 30-80 degrees C, relux stirring time is 2-6 hours, cooling, diluting, carrying out suction filtration, washing with hydrochloric acid followed by water, drying in vacuum at 60-80 degrees C to obtain oxidized carbon nanotubes, adding acid chloride agent, stirring at relux 60-80 degrees C temperature, relux stirring time is 12-48 hours, distilling out excess acid chloride agent to obtain acid chloride carbon nanotube.    USE - The catalyst is useful in direct methanol fuel cell (claimed).    ADVANTAGE - The method is simple; contains mild reaction conditions; synthesizes small, uniformly dispersed particle; economical and suitable for industrial production. The catalyst has high activity, stability, large surface area, carbon monoxide poisoning resistance.    DETAILED DESCRIPTION - Preparing catalyst comprises (i) adding carbon nanotubes into concentrated sulfuric acid and concentrated nitric acid, stirring uniformly, where stirring temperature is 30-80 degrees C, relux stirring time is 2-6 hours, cooling, diluting, carrying out suction filtration, washing with hydrochloric acid followed by water, drying in vacuum at 60-80 degrees C to obtain oxidized carbon nanotubes, (ii) adding oxidized carbon nanotubes to acid chloride agent, stirring at relux 60-80 degrees C temperature, relux stirring time is 12-48 hours, distilling out excess acid chloride agent to obtain acid chloride carbon nanotube, (iii) mixing acid chloride carbon nanotube and phosphoric acid, stirring at 70-90 degrees C for 12-24 hours, cooling, carrying out suction filtration, washing with water, drying in vacuum to obtain phosphoric acid functional carbon nanotubes, (iv) taking phosphoric acid functional carbon nanotubes in weighing bottle, adding deionized water, ultrasonic dispersing to obtain mixed solution (A), adding precursor of platinum catalyst to solution (A), ultrasonic dispersing to obtain solution (B), and (v) slowly adding reducing agent to solution (B) under ultrasonic shaking to obtain platinum/ phosphorus-carbon nanotube catalyst solution. An INDEPENDENT CLAIM is also included for catalyst, prepared by the above method.