The invention discloses a preparation method of stannic oxide microspheres of an oriented connection microstructure. The preparation method concretely includes the steps that 14 mL of ethyl alcohol and 2 mL of water are placed into a reaction container, 0.1 mL of 37%hydrochloric acid solution is then added for even stirring and mixing, 0.7 g of SnC12.2H2O is added under the stirring condition, and a reaction precursor solution is obtained through ultrasonic treatment after even stirring and mixing; the reaction precursor solution is placed into a hydrothermal reaction kettle, the packing ratio of the hydrothermal reaction kettle is 60-80%, then hydrothermal reaction is performed for 12-24 h at 180-200 DEG C, and precipitate is obtained through centrifuging after the precursor solution is cooled to a room temperature and dried for 6-12 h at 60-80 DEG C to obtain the stannic oxide microspheres of the oriented connection microstructure, wherein the stannic oxide microspheres are composed of nanometer rods of 10-20 nm, and the hierarchical structure size is 0.5 micrometer-1 micrometer. The preparation method is simple and high in repetition rate, and the obtained stannic oxide microspheres are uniform in size and has high crystalline degree. Especially, the prepared stannic oxide microspheres are of the oriented connection microstructure, in this way, the migration rate of electrons in materials can be greatly increased, and great application value is achieved in the aspects of photoelectricity and photocatalysis.