To investigate the effect of exogenous additions on the characteristics of soil drying and shrinkage crack. Three utilization types of soil samples were selected for paddy field, dry field and forest land and four exogenous additives including quicklime (1 g/kg), fulvic acid (10 g/kg), fish pond sediment (250 g/kg), and biochar (15 g/kg), were added to conduct soil drying and shrinkage tests. The results showed that, in addition to quicklime, the change trend of soil drying shrinkage crack characteristics of different land types under different soil amendment treatments was very consistent, and the surface density, length density and average width of crack showed the change trend of cultivated layer paddy field＞dry field＞forest land, and plow bottom paddy field＞forest land＞dry field. Quicklime has no significant effect on soil dry shrinkage crack characteristics; fulvic acid increased the surface density of soil dry shrinkage cracks and the average width, but had no significant effect on the length density of soil dry shrinkage cracks; fish pond sediment increased the surface density of soil cracks and the length density, but had no effect on the average width of dry shrinkage cracks; biochar reduced the surface density of soil cracks and the average width of cracks, but increased the average length density of cracks. Compared with the blank control, the degree of influence of different exogenous additives on the density of soil fracture surface were as follows: Cultivated layer fish pond sediment＞biochar＞fulvic acid＞quicklime, plow bottom fulvic acid＞fish pond sediment＞biochar＞quicklime; the degree of influence on fracture length density was as follows: Cultivated layer biochar ＞fish pond sediment＞quicklime＞fulvic acid, plow bottom biochar＞fish pond sediment＞fulvic acid＞quicklime in the plough bottom layer. Exogenous additives have an important effect on the characteristics of soil cracks. Quicklime has no significant effect on the development of soil cracks. Fulvic acid and fish pond sediment can promote the development of soil cracks, and biochar can inhibit the development of soil cracks. The results can be used to improve the physical and chemical properties of soil using improved soil agents in agricultural production.