A high-density information storage apparatus using electron emission and methods of writing, reading and erasing information using the same are provided. The high-density information storage apparatus includes a lower electrode, a photoconductive layer and a recording medium sequentially provided on the lower electrode, a conductive layer converting unit for making the photoconductive layer conductive, a data write and read unit for writing data to the recording medium or reading data from the recording medium, a data loss preventing unit for preventing loss of data during data write and read operations, and a power supply connected to the lower electrode and the data write and read unit, for supplying voltage necessary for reading and writing data.