Novel tube-like Y2Sn2O7:Tb3+ crystals with pyrochlore structure have been successfully synthesized via a hydrothermal route. The experimental results show that ammonia plays a key role in the fabrication of Y2Sn2O7:Tb3+ with tube-like morphology. The photoluminescence spectra indicate that the tube-like Y2Sn2O7:Tb3+ crystals emit strong green light at 543 nm under UV excitation. The growth mechanism of tube-like Y2Sn2O7:Tb3+ crystals is proposed.