Character recognition is one of common pattern recognition study. There are many object used in pattern recognition, such as Japanese alphabet character, which is a very complex character compared to common Roman character. This research focus on pattern recognition of Japanese character handwriting, Katakana. The pattern recognition process of a letter of the alphabet uses Airy Zeta Function, with its input file is a .bmp file. User can write directly on an input device of the system. The testing of the system examines 460 letter characters. The first testing that examines 230 characters result in an accuracy of 55,65%, whilst the second testing that examines 460 characters produces an accuracy of 64,56% in recognizing the letters. These accuracy are much determined by the quantity of training. The approach of pattern recognition is a statistical approach, where more pattern of letters are trained and saved as a reference, more intelligent the system . The implementation of Airy zeta function methods in recognizing Japanese letter pattern is able to produce high accuracy level.