The soybean variety DLL1172 is disclosed. The invention relates to seeds, plants, plant cells, plant tissue, harvested products and soybean lint as well as to hybrid soybean plants and seeds obtained by repeatedly crossing plants of variety DLL1172 with other plants. The invention also relates to plants and varieties produced by the method of essential derivation from plants of DLL1172 and to plants of DLL1172 reproduced by vegetative methods, including but not limited to tissue culture of regenerable cells or tissue from DLL1172.