To investigate the clinical effect of nano-composite resin combined with transparent preformed crown in the repair of maxillary deciduous incisors. Methods A total of 85 children who received oral repair in our hospital from June 2021 to June 2022 were selected as the research objects. They were divided into control group (n =42) and observation group (n =43) by random number table method. The control group was filled with nano-composite resin, and the observation group was treated with nano-composite resin combined with transparent preformed crown aesthetic restoration. The success rate of repair, aesthetic indicators and oral function were compared between the two groups. Results There was no significant difference in the success rate of repair between the two groups at 3 months after repair (P >0.05). The success rate of repair in the observation group was higher than that in the control group at 6 and 12 months after repair (P <0.05). The pink and white esthetic scores and facial aesthetic indexes in the observation group were higher than those in the control group at 3, 6 and 12 months after repair (P <0.05). The scores of aesthetics, masticatory function and language in the observation group were higher than those in the control group (P <0.05). Conclusion The clinical effect of nano-composite resin combined with transparent preformed crown in the repair of maxillary deciduous incisors is good, which can achieve better repair effect and aesthetic value, and effectively improve the oral function of pa tients.