We report what we believe to be the first demonstration of laser operation with a novel laser material of Yb3+-doped Gd2SiO2(Yb:GSO)pumped by a laser diode at 940 nm. We obtained a low lasing threshold of 1.27 kW/cm2 with the center wavelength of 1090 nm, which is lower than the value of 1.53 kW/cm2 predicted for Yb:YAG. The maximal output power of 360 mW was obtained with a 2% output, which corresponds to a slope efficiency up to 19%.