A strain sensor with high flexibility using ionic liquid is proposed for sensing movements of human body. The resistance strain sensor is constructed from a silicon tube filled fully with a mixture of aqueous sodium chloride and glycerin sealed gold-coated electrodes. When an external force is applied to the sensor, the silicon tube deforms resulting in a change in the sensor resistance value. The proposed sensor was fabricated and experimentally characterized under several working conditions. Good performance was demonstrated in detecting the movement of human leg and fingers. The proposed simple sensor has high potential in wearable applications.