This paper reported the growth of potassium titanyl phosphate (KTiOPO4 or KTP) crystals by hydrothermal method. The KTP crystals were grown in 2.0 mol/l K2HPO4 + 0.1 mol/l KH2PO4 + 1 wt% H2O2 solution using crushed flux KTP crystals as nutrients. The KTP crystals with dimension up to 14.5 x 28 x 17 mm(3) and excellent quality were obtained. The growing rate of KTP crystals along (011) was 0.15 mm/day. The damage threshold value of the grown KTP crystal was up to 9.5 GW/cm(2) for 1064nm (TEM00, 10ns). The transmittance was over 80% in the range of 450-2500 nm. (c) 2006 Elsevier B.V. All rights reserved.