| Title | Article Coverage | Review Coverage |
| Odrodzenie i reformacja w Polsce | Vol. 1 (1956) to vol. 49 (2005) | Not applicable or not currently indexed |
| Oeuvres et critiques | Vol. 1 (1976) to vol. 35, no. 2 (2010) | Vol. 15 (1990) to vol. 29, no. 2 (2004) |
| Old English newsletter | Vol. 1 (1967) to vol. 42, no. 1-2 (2009) | Not applicable or not currently indexed |
| Olifant | Vol. 1 (1973) to vol. 21, no. 3-4 (1997) | Vol. 15 (1990) to vol. 22, no. 4 (2003) |
| The opera journal | Vol. 1 (1968) to vol. 39, no. 3 (2006) | Not applicable or not currently indexed |
| The opera quarterly | Vol. 1, no. 1 (1983) to vol. 26, no. 1 (2010) | Vol. 7 (1990) to vol. 22, no. 1 (2007) |
| Opportunities for research in Renaissance drama | No. 4 (1958) to no. 5 (1959-1960) (journal title ended) | Not applicable or not currently indexed |
| Oral tradition | Vol. 1 (1986) to vol. 24, no. 2 (2009) | Not applicable or not currently indexed |
| Orbis litterarum | Vol. 33 (1978) to vol. 65, no. 4 (2010) | Vol. 45 (1990) to vol. 60, no. 3 (2005) |
| Orbis musicae | Vol. 1 (1971) to vol. 13 (2003) | Not applicable or not currently indexed |
| Osiris | Vol. 1 (1985) to vol. 25 (2010) | Not applicable or not currently indexed |
| Österreichische Akademie der Wissenschaften. Philosophisch-historische Klasse. Denkschriften | Vol. 76 (1957) to vol. 219 (1991) | Not applicable or not currently indexed |
| Österreichische Akademie der Wissenschaften. Philosophisch-historische Klasse. Sitzungsberichte | Vol. 225 (1948) to vol. 685, no. 18 (2000) | Not applicable or not currently indexed |
| Oud Holland | Vol. 1 (1883) to vol. 123, no. 2 (2010) | Vol. 104 (1990) to vol. 120, no. 3-4 (2007) |
| The Oxford art journal | Vol. 1 (1978) to vol. 33, no. 1 (2010) | Not applicable or not currently indexed |
| Oxford German studies | Vol. 1 (1966) to vol. 39, no. 3 (2010) | Not applicable or not currently indexed |
| Oxford journal of archaeology | Vol. 1 (1982) to vol. 29, no. 3 (2010) | Not applicable or not currently indexed |
| Oxford Slavonic papers | Vol. 1 (1950) to vol. 33 (2000) | Not applicable or not currently indexed |