Although intrapleural administration of fibrinolytics is an important treatment option for the management of empyema, the addition of fibrinolytics failed to reduce the need for surgery and mortality in previous randomized controlled trials. This study aimed to investigate the effects of administrating fibrinolytics in the early phase (within 3 days of chest tube insertion) of empyema compared with late administration or no administration. We used the Japanese Diagnosis Procedure Combination Inpatient Database to identify patients aged ≥16 years who were hospitalized and underwent chest tube drainage for empyema. A 1:2 propensity score matching and stabilized inverse probability of treatment weighting were conducted. Among the 16265 eligible patients, 3082 and 13183 patients were categorized into the early and control group, respectively. The proportion of patients who underwent surgery was significantly lower in the early fibrinolytics group than in the control group; the odds ratio (95% confidence interval) was 0.69 (0.54-0.88) in the propensity score matching (P = 0.003) and 0.64 (0.50-0.80) in the stabilized inverse probability of treatment weighting analysis (P < 0.001). All-cause 30-day in-hospital mortality, length of hospital stay, duration of chest tube drainage, and total hospitalization costs were also more favourable in the early fibrinolytics group. The early administration of fibrinolytics may reduce the need for surgery and death in adult patients with empyema.