A novel single layer, dual linear polarized unit cell is introduced for a quad-band reflectarray antenna in the Ku-band centered around 12, 13, 14, and 15.5 GHz. The unit-cell design is such that the resultant reflectarray antenna can be considered as four different reflectarray antennas, each with a specific beam shape, sharing one aperture. As proof-of-concept, two quad-band reflectarray antenna prototypes having a plate size of 20 x 20 cm(2) have been designed and fabricated each with a certain beam direction versus frequency. Measurement and simulation results show satisfactory performance of both reflectarray antennas at each frequency.