Herein we report the surfactant-thermal method to prepare two novel one-dimensional mercury selenidostannates, [DBUH]2[Hg2Sn2Se6(Se2)] (1) and [DBUH]2[Hg2Sn2Se7] (2), where DBU = 1,8-diazabicyclo[5.4.0]undec-7-ene, by applying PEG-400 as the reaction medium. It is worth noting that 1 is kinetically stable and can be transformed into thermodynamically stable phase 2 under a longer reaction time. Our strategy "growing crystalline materials in surfactants" could open a new door to preparing novel crystals with diverse structures and interesting properties.