This paper describes the initial concept of functional electrical stimulation (FES) for foot drop injury based on the arm swing motion. The prototype was an effort to improve the existing FES available in the market that are facing problems due to the error of detecting a step intention, especially in the acute stage of foot drop injury due to stroke. The development of the device was divided into two main phases: hardware design and testing. Hardware phases consisted of the design of the electronic structure and parts such as accelerometer ADXL335 and programming for PIC18F4520. Initial testing was conducted with six normal subjects and one foot drop patient subject in order to identify the functional performance of the prototype. The result shows that the gait sensing placement of the prototype FES was successfully controlled by using the arm swing movement.