Provided are an arbiter capable of improving memory access efficiency in a multi-bank memory, a memory access arbitration system including the arbiter, and an arbitration method thereof, where the arbiter detects requests that are not included in a busy bank, and allows the requests corresponding to a bank receiving the largest number of pending requests priorities; and write request information generated by masters is stored in a predetermined buffer to be output as additional master request information, and provides the corresponding master with an opportunity to generate new request information.