The invention belongs to the technical field of seepage control and discloses a composite geomembrane anti-seepage construction splicing method. The method comprises the following steps of: removing a non-woven fabric on the surface of a composite geomembrane to be spliced so as to expose membrane surfaces; coating an adhesive between the two membrane surfaces to be spliced and on the parts of the two membrane surfaces to be spliced respectively, wherein the parts are extented to corresponding parent materials for no less than 1.5cm; and pressurizing to bond the membrane surfaces. The method has the advantages that: (1) the non-woven fabric on the surface of a connected edge is removed by using an angle grinder to drive a circular steel brush or a steel wire wheel with good effect and high efficiency; (2) after the non-woven fabric on the surface of the connected edge is removed, the adhesive is facilitated to permeate onto the surface of the membrane, and after bonding, the adhesive cannot permeate into a passage, so that the anti-seepage effect is improved and the dosage of the adhesive is reduced; (3) the bonded surfaces are extented to the parent material for no less than 1.5cm, so that the part with the weak strength of the connected edge is eliminated and the bonding shear strength of the connected edge is the same as the strength of the parent material; and (4) the method is suitable for laying irregular shapes and repairing the defects of the composite geomembrane during composite geomembrane anti-seepage construction.