By high-temperature solution method, BIBO crystal with high optical quality is grown out successfully. The size reached 24 mm×19 mm×35 mm, and the weight is 48 g. For BIBO crystal the orientation, as well as the refractive index on the main optical axis, is measured. The third harmonic generation(THG) property of 1064 nm in BIBO crystal, including phase-matching(PM) angle, effective nonlinear optical coefficient(d eff), angler acceptance, and walk-off angle is discussed. The results show that the optimum configuration for the THG of 1064 nm in BIBO crystal is at the Type-I PM direction(137.7°,130°), which has a d eff of 3.60 pm/V. Among PM directions located in principal planes,(146.4°,90°) has the largest d eff value, i.e. 3.16 pm/V. In extra-cavity THG experiments of 1064 nm, the conversion efficiency of(146.4°,90°) BIBO crystal reached 39.5 %, and the half-width of its angular acceptance is measured to be 0.22 mrad·cm, which is in good consistent with the calculated value, 0.175 mrad·cm. For(33.6°,90°) BIBO crystal, because the deff is very small(0.31 pm/V), its THG conversion efficiency is lower than 5%.