Provided is a method of nitriding a surface of aluminum or aluminum alloy by cold spraying. That is, a surface of aluminum or aluminum alloy is coated by cold spraying, and then a heat treatment is performed thereon at low temperature for a short time period. Accordingly, the method is suitable for nitriding a surface of Al and Al alloy, which is very difficult to be nitrided, at low production costs. The method includes removing a foreign material from a surface of a mother substrate comprising Al or Al alloy; cold spraying 15 to 50 wt% of a catalyst powder and 50 to 85 wt% of a coating agent powder on the surface of the mother substrate to form a coating layer; and heat treating the coating layer at a temperature of 450 to 630 °C in a nitrogen atmosphere for 2 to 24 hours.