The development of a low-crosstalk 2 x 2 digital optical switch is reported. The device is a composite structure composed of four low-drive-voltage Y-branch digital optical switches and an asymmetric X-junction. A minimum crosstalk level of -37dB was achieved in the TM mode, while in the TE mode the level was -42dB. The voltage-total-length product is identical to that of a conventional 2 x 2 digital optical switch operating at a given level of crosstalk.