The invention provides shrinkage compensating type high-performance mortar for grooving method closure grouting. The shrinkage compensating type high-performance mortar is characterized by being formed by compounding polymer gelatine powder, silica powder, a superfine micro-powder expanding agent, a high-performance water reducing agent, aggregate and a binding material through the processes of powder drying, dispersion machine pre-dispersion, fiber pre-mixing and vacuum sealing; the mortar is prepared from, by mass, 1.5-3% of polymer gelatine powder, 0.8-1.2% of silica powder, 1.25-2.5% of superfine micro-powder expanding agent, 0.10-0.14% of high-performance water reducing agent, 69-75% of aggregate and 12.5% of binding material (containing cement). The mortar has the advantages of good micro-expansibility, water retaining performance, waterproofness, easy binding and the like, and is suitable for grooving method chemical grouting construction on cracks and expansion joints, the surface of a dug dovetail-shaped groove is effectively closed, grout leakage and runout can be avoided, and grouting quality is improved.