The invention provides a resistive random access memory having a heterojunction structure. A resistive random access memory cell of the resistive random access memory includes: a lower electrode, a resistive layer formed on the lower electrode, and an additional oxide layer formed on the resistive layer. The heterojunction structure is formed by the additional oxide layer and the resistive layer, the lower electrode is connected with one of word lines or bit lines of the resistive random access memory by a metal interconnection, the heterojunction structure is connected with the other one of the word lines or the bit lines of the resistive random access memory by the metal interconnection, and the word lines and the bit lines are in a vertical and horizontal cross state. The invention also provides a reading method of the resistive random access memory having the heterojunction structure. With the resistive random access memory having the heterojunction structure, the reading method comprises the following steps: a voltage of +0.5 Vread is added to one of the corresponding word lines or the corresponding bit lines in the resistive random access memory cell, a voltage of -0.5 Vread is added to the other one of the corresponding word lines or the corresponding bit lines in the resistive random access memory cell, and then data is read. The reading method has the advantages of stability, reliability, and accurate reading.