The disclosure provides a method for obtaining optimal operating condition of a resistive random access memory (RRAM). The method includes: retrieving an RRAM chip and performing a forming operation and an initial reset operation thereto based on a first operating condition; segmenting the RRAM chip into blocks; performing a set operation to each of the blocks based on various operating voltages; obtaining a fail bit value of each of the blocks; generating an operating characteristic curve related to the RRAM chip based on the fail bit value of each of the blocks and the operating voltages, wherein the operating characteristic curve has a lowest fail bit value and an operating voltage window; and when the lowest fail bit value and the operating voltage window satisfy a first condition and a second condition, respectively, determining the first operating condition is an optimal operating condition of the RRAM chip.