According to embodiments of the present invention, there are provided a TFT array substrate, a method for manufacturing the TFT array substrate and an electronic device. The method for manufacturing the TFT array substrate includes: a first patterning process, in which a pattern of a pixel electrode formed by a first transparent conductive layer and patterns of a drain electrode and a source electrode that are separated from each other and a data line, which are formed by a first metal layer, are formed on a transparent substrate; a second patterning process, in which a pattern of a gate insulating layer and a pattern of an active layer formed by a transparent oxide layer are formed on the transparent substrate subjected to the first patterning process; and a third patterning process, in which a pattern of a common electrode formed by a second transparent conductive layer and patterns of a gate electrode and a gate line which are formed by a second metal layer are formed on the transparent substrate subjected to the second patterning process.