Abstract This paper presents an optimal Bangla Keyboard Layout, which distributes the load equally on both hands so that maximizing the ease and minimizing the effort. Bangla alphabet has a large number of letters, for this it is difficult to type faster using Bangla keyboard. Our proposed keyboard will maximize the speed of operator as they can type with both hands parallel. Here we use the association rule of data mining to distribute the Bangla characters in the keyboard. First, we analyze the frequencies of data consisting of monograph, digraph and trigraph, which are derived from data wire-house, and then used association rule of data mining to distribute the Bangla characters in the layout. Experimental results on several data show the effectiveness of the proposed approach with better performance. Keywords: monograph, digraph, trigraph, association rule, data mining, hand switching, support, confidence. 1 Introduction The usefulness of computer is increasing rapidly. It is the fastest growing industry in the world. New invention of technologies makes it faster. The billions of instructions can be done within a second nowadays. But the technology of input device like keyboard has not been changed much. The typing speed is very slow in respect of computer’s other devices. Its main cause is the complex and insufficient keyboard layout and human limitations [8] [9]. A scientific keyboard layout with equal hands load and maximum hand switching can reduce this problem. The use of Bangla is increasing day by day in everyday life. Specially in data entry and printing sector. But there is no scientific Bangla keyboard layout at present and very few research works have been done in this field. We use the concept of data mining association rule to design Bangla keyboard layout that shows optimal and better performance than the existing keyboard layout. In this paper we have tried to design a Bangla keyboard layout using the association rule of data mining. We have collected the data from various Bangla documents and we have used the association rule to extract the association of Bangla letters each other. And finally we have designed a Bangla keyboard layout with equal hands load and maximum hand switching.