Single crystals of strontium barium niobate (SBN) solid solution, (SrxBa1-x)(1-y)(Nb2O5)(y), 0.75 greater than or equal tox greater than or equal to0.40, 0.5050 > y > 0.4975, were grown by the floating zone method. There are two series of the crystals. x varies and y is fixed at 0.5 in the first series of crystals, x is fixed at 0.61 and y varies in the second series. The typical size of the grown crystal is 5 mm in diameter and 70 mm in length. All crystals, regardless of the compositions, revealed the facet parallel to the c-plane and the clear striations. A part around the crystal can be easily broken due to hoop stress. The spontaneous growth-direction of SBN is (0 0 1). The congruent melting composition of SBN is revealed by employing a zone-melting method at the final stage of growth experiments. It is (Sr-0.61 Ba-0.39)(0.5015)(Nb2O5)(0.4985). The absorption edges of the crystals in both series are around 360 nm and are shifted by 10 nm toward blue in comparison with those of the crystals grown by CZ method.