Abstract: Based on single -walled carbon nanotube network thin films deposited on flexible polyethytlene films with layer-by -layer self-assembly method,strain sensors were developed with microelectronic process.Both the films and the sensors were characterized.SEM images show the films are uniform.The experimental data show the films have good electric conductivity property and the resistance of the film decays exponentially with the increase of the number of layers.The sensors show different resistivity for different strains with prompt and nearly linear response,as well as they achieve their strain sensitivity up to 4.25.The stability is remarkably improved by coating protective film on the surface of the device,with which device becomes less vulnerable to humidity and lightness.These flexible sensors can be used on curved surfaces.