The invention discloses a method for preparing laboratory grouting cement soil. The cement grouting soil is composed of soil, cement and water. The preparation method comprises the following steps: airing and breaking soil, passing through a 2mm sieve, and preparing wet soil according to the natural moisture content of 25%; infiltrating the prepared soil in a sealed vessel overnight; blending cement accounting for 20% of the mass of the wet soil into cement paste according to a water cement ratio of 0.5, and pouring a mixture of the wet soil and the cement paste into a stirrer for stirring; weighing multiple parts of the mixture based on the weight of 825g per part; placing each part of the cement in a cylindrical mold with the diameter of 70mm and the height of 200mm, and compacting for 50 times by using a compacting hammer. The finally prepared test block is the cylinder with the diameter of 70mm and the height of 100mm, test block materials can be placed in the mold at a time, the cement soil test block with high integrity is formed due to one-time compaction, the integrity of the cement soil test block is enhanced, the quantity of fault fissures is reduced, and the compressive strength of the cement soil is improved.