Pius X
- Short biographical profile from the 1911 Encyclopædia Britannica, published during his papacy.
- http://encyclopedia.jrank.org/PIG_POL/PIUS_X.html

Si Diligis
- An allocution of Pope Pius XII, read on the occasion of the canonization of Pope St. Pius X, in 1954.
- http://ewtn.com/library/PAPALDOC/P12SIDIL.HTM

Museo San Pio X
- Museum in Salzano, where Giuseppe Sarto (later Pius X) was parish priest. Description of the museum, and a multipart biography of Pius X. In Italian, English, Spanish, and German.
- http://www.museosanpiox.it/

Catholic Online: St. Pius X
- Short biography.
- http://www.catholic.org/saints/saint.php?saint_id=313

Vietnamese Eucharistic Youth Society: St. Pius X
- Short biography, suited to children.
- http://www.tntt.org/vni/tlieu/saints/St0821.htm

Catholic Encyclopedia: Pope Pius X
- Long article on the reigning pontiff at the time the encyclopedia was published.
- http://www.newadvent.org/cathen/12137a.htm

Pope St. Pius X (1835-1914)
- Fairly long article, from the book "Lives of Saints," published by John J. Crawley.
- http://www.ewtn.com/library/MARY/PIUSX.htm

St. Pius X, Our Patron Saint
- Short biographical portrait, from St. Pius X Parish, Essex Junction, Vermont.
- http://homepages.together.net/~stpius/patron.htm

Popes Through the Ages: St. Pius X
- Account of his pontificate.
- http://www.cfpeople.org/Books/Pope/POPEp255.htm

Patron Saints Index: Pope Pius X
- Illustrated profile, with links.
- http://www.catholic-forum.com/saints/saintp06.htm