The invention discloses an etching method and a method of manufacturing a printed circuit board by utilizing the etching method.According to the etching method of the invention, an object to be etched is provide and a resist layer is stacked on the object.The resist layer is equipped with a fuse pattern and a slit formed thereon and the fuse pattern is separated by the slit.Then the object is etched until the fuses formed corresponding to the fuse pattern and exposed out of the slit are separated form each other.Since the amount of the etching is directly detected and the etching process can be stopped, fine circuit patterns can be formed by the accurate etching process.