A thin film transistor array panel and a manufacturing method therefor. A shorting bar for connecting a thin film transistor with data lines is formed separate from the data lines, and then the data lines and the shorting bar are connected through a connecting member. As a result, all the data lines are floated during manufacture, so that variation in etching speed between data lines does not occur. Since variation in etching speed between the data lines can be prevented, performance deterioration of the transistor caused by a thickness difference in the lower layer of the data line can be prevented, as can resulting deterioration in display quality. Also, the influence of static electricity can be reduced or eliminated. Furthermore, since the data lines and the shorting bar are connected to each other, the generation of static electricity can be prevented or reduced, and quality testing is more readily performed.