| Domain | Name | Category | Type |
| IPR001631 | DNA topoisomerase I | Family | Family |
| IPR008336 | DNA topoisomerase I, DNA binding, eukaryotic-type | Domain | Domain |
| IPR011010 | DNA breaking-rejoining enzyme, catalytic core | Family | Homologous superfamily |
| IPR013030 | DNA topoisomerase I, DNA binding, N-terminal domain 2 | Family | Homologous superfamily |
| IPR013034 | DNA topoisomerase I, DNA binding, N-terminal domain 1 | Family | Homologous superfamily |
| IPR013499 | DNA topoisomerase I, eukaryotic-type | Domain | Domain |
| IPR013500 | DNA topoisomerase I, catalytic core, eukaryotic-type | Domain | Domain |
| IPR014711 | DNA topoisomerase I, catalytic core, alpha-helical subdomain, eukaryotic-type | Family | Homologous superfamily |
| IPR014727 | DNA topoisomerase I, catalytic core, alpha/beta subdomain | Family | Homologous superfamily |
| IPR018521 | DNA topoisomerase I, active site | Site | Active site |
| IPR025834 | Topoisomerase I C-terminal domain | Domain | Domain |
| IPR036202 | DNA topoisomerase I, DNA binding, eukaryotic-type, N-terminal domain superfamily | Family | Homologous superfamily |