Objective To observe the clinical effect of Guanggu Jisheng decoction on the treatment of coronavirus disease 2019 (COVID-19) during recovery stage. Methods A total of 122 convalescent COVID-19 patients in Guanggu Branch of Maternity and Child Healthcare Hospital of Hubei Province were treated with Guanggu Jisheng decoction for 3 consecutive courses, each course lasting 3 days. The changes of traditional Chinese medicine (TCM) syndromes before and after treatment were compared. Scores were recorded according to the laboratory testing and the severity of symptoms (no symptom, mild, common and severe) to investigate the clinical curative effect of Guanggu Jisheng decoction on the treatment of convalescent COVID-19. Results According to the TCM syndrome scores, after one course of treatment (3 days), the total effective rate was 75.41% (92/122), with the effective rate being 31.97% (39/122), the significant efficiency being 21.31% (26/122), and the clinical recovery rate being 22.13% (27/122). After two courses of treatment (6 days), the total effective rate was 86.89% (106/122), with the effective rate being 32.79% (40/122), the significant efficiency being 28.69% (35/122), and the clinical recovery rate being 25.41% (31/122). After three courses of treatment (9 days), the total effective rate was 88.52% (108/122), with the effective rate being 16.39% (20/122), the significant efficiency being 31.15% (38/122), and the clinical recovery rate being 40.98% (50/122). The symptoms of cough, fatigue, shortness of breath and sweating were significantly improved. No patients turned positive again from negative of respiratory pathogen nucleic acid. Conclusion Guanggu Jisheng decoction has a good clinical effect on convalescent COVID-19 patients. It can significantly improve the clinical symptoms.