The invention relates to a device for paddy field saline-alkali soil vertical sampling. The device is composed of a cylinder barrel, a barrel cover, a metal pendant, soil taking holes, rubber plugs and a short rod soil auger, and is characterized by simple structure, and low material cost. During use, the sampling barrel is inlaid in a paddy field, and in the barrel, sampling by the short soil auger is simple and convenient. The sampling barrel can be placed in the field for continuous use for a long time, and the sampling error can be reduced. The invention can also be applied in paddy field growing season and wetland soil sampling. Specifically, the invention can be used for analysis of paddy field or wetland vertical gradient of saline ion migration, nutrient distribution rule, root distribution and microorganism distribution and the like of soil sample collection. The device provided in the invention has the advantages of simple structure, low cost, convenient installation, small sampling error, easy mastery by operators, and wide application range, etc., and has a promotion value.