Objective To investigate the aesthetic effect of nano-light-cured composite resin filling in the repair of wedge-shaped defects. Methods A total of 65 patients with wedge-shaped defects of maxillary premolars admitted to our hospital from July 2022 to July 2023 were selected as the research objects and divided into control group (32 patients) and observation group (33 patients) according to the random number table method. The control group was filled with resin-modified light-cured glass ionomer material, and the observation group was filled with nano-light-cured composite resin material. The success rate of filling repair, aesthetic effect and periodontal health indicators were compared between the two groups. Results The success rate of filling repair in the observation group was 96.97%, which was higher than 78.13% in the control group (P <0.05). The pink esthetic score and white esthetic score of the observation group after filling repair were higher than those of the control group (P <0.05). The gingival sulcus bleeding index, plaque index and probing depth in the observation group were better than those in the control group (P <0.05). Conclusion The success rate of filling repair of wedge-shaped defects with nano-light-cured composite resin filling is high, with good aesthetic effect and reliable long-term effect.