The invention discloses a testing method for a water permeability coefficient of a cement pavement. The testing method comprises the following steps: (1) after uniformly mixing a component A and water, uniformly coating a mixture on a waterproof ring of a pre-set water penetration meter chassis; (2) after uniformly mixing a component B and water, blending to obtain paste with the thickness of 10cm; coating the paste on the component A to ensure that the edge of a water penetration meter is uniformly coated; (3) carrying out a water permeability test. When the testing method disclosed by the invention is used for constructing, the component A is directly coated on the ground, can be tightly stuck with the cement ground and also can be sealed with a component of the component B very well; the thickness of coating the component A on the cement ground is relatively thin and the component A does not need to be cleaned after construction is finished, so that the time and resources are saved;the component B and the component A are tightly combined together, have good sealing performance, are easy to store, are not stuck on hands and are easy to recycle and pollution to the cement pavement is not caused; and meanwhile, a product is environmentally friendly and has no toxicity and no harms and strong operability.