The porous K4Nb6O17 microsphere with large surface area (86.6 m(2)/g) has been successfully synthesized for the first time by the homogeneous precipitation method using urea. The obtained product was characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and nitrogen adsorption-desorption isotherm analysis. The photocatalytic experiments showed that the porous K4Nb6O17 microsphere not only had a high activity for the degradation of Rhodamine B, two times higher than that of the commercial Degussa P25 TiO2, but also had much higher activity for generating H-2 with a rate of 3.0 mmol/h under UV light irradiation. The high activity of the K4Nb6O17 microsphere was mainly attributed to its porous structure and high specific surface area. (C) 2011 Elsevier B.V. All rights reserved.