Manufacturing method of photoresist patten and manufacturing method of dispaly panel

A method for forming a photoresist pattern and a method for manufacturing a display panel are provided to manufacture the display panel without a mask, thereby lowering the manufacturing cost. A gate pattern having a gate line and a gate electrode(21) is formed on a substrate(10) by using a first conductive layer. A gate insulating layer(30), an amorphous silicon layer(240), an impurity-doped amorphous silicon layer(245), a second conductive layer(250), and a photoresist are sequentially formed over the substrate. The photoresist includes a channel region, through which a channel of a thin film transistor is to be formed, and a data pattern region, through which a data pattern having electrodes of the thin film transistor and a data line is to be formed. The photoresist is subjected to light exposure to form a stepped photoresist pattern(221), wherein the light exposure is performed in the channel region and the data pattern region a different number of times respectively. An etching process is performed on the resultant substrate including the stepped photoresist pattern to form the thin film transistor and the data line. A passivation film is formed on the resultant substrate, having a pixel contact hole which exposes a portion of a drain electrode. A pixel electrode is formed on the passivation film and electrically connected to the drain electrode through the pixel contact hole.