A bit cell of an organic memory is provided. The bit cell of the organic memory comprises an organic memory cell, a first transistor, a current mirror and a second transistor. To connect the organic memory cell to a data line, the first transistor is activated for reading and the second transistor is activated for writing. Furthermore, the first transistor has a greater size than the second transistor. Therefore, a fast processing time in writing and a large conduction current in reading are catered for. In addition, the current mirror amplifies the conduction current in reading and increases the capacity for resisting the interference by adjacent bit cell.