OBJECTIVE To mine and analyze the adverse drug events （ADE） signals of two camptothecin topoisomerase 1 inhibitors， i.e. irinotecan and topotecan， and to provide reference for clinical medication safety. METHODS Based on the U.S. Food and Drug Administration Adverse Event Reporting System （FAERS） database， ADE report data for the aforementioned two drugs were extracted from January 1， 2004 to March 31， 2023. After processing the data， signal mining was conducted by using the reporting odds ratio in conjunction with the Bayesian confidence propagation neural network， followed by analysis. RESULTS A total of 14 738 relevant ADE reports were screened， among which 11 483 were associated with irinotecan and 3 255 with topotecan. The ADE reports for irinotecan were predominantly male， whereas for topotecan， they were predominantly female； the age of patients using the two drugs mainly concentrated in 45-＜75 years old. A total of 847 signals were detected， involving 24 system organ classes （SOCs）. Among them， 565 signals of irinotecan were detected， involving 24 SOCs， primarily concentrating on gastrointestinal disorders， general disorders and administration site conditions， blood and lymphatic system disorders； the most frequently reported ADE was diarrhea， and the ADE with the strongest signal intensity was cholinergic syndrome. A total of 282 signals of topotecan were detected， involving 22 SOCs， primarily concentrating on general disorders and administration site conditions， investigations， blood and lymphatic system disorders， and gastrointestinal disorders； the most frequently reported ADEs were death and anemia， and the ADE with the strongest signal intensity was febrile bone marrow aplasia. ADE signals for irinotecan such as metastatic colorectal cancer， peripheral sensory neuropathy， steatohepatitis， and those for topotecan such as iris atrophy， retinal degeneration， vitreous hemorrhage， were not documented in their respective drug instruction. CONCLUSIONS ADEs of irinotecan and topotecan primarily involve the digestive and hematologic systems， warranting close clinical monitoring. Cholinergic syndrome caused by irinotecan should be concerned. In addition， patients receiving irinotecan should also be monitored for ADE such as metastatic colorectal cancer， peripheral sensory neuropathy， steatohepatitis， and proteinuria； for patients using topotecan， enhanced surveillance of ocular diseases is recommended to ensure medication safety.