Jessop Family
- Family history of Graham and Fiona Jessop from Norwich, England.
- http://freespace.virgin.net/hunston.tv/

Jandebeur Family
- For the ancestors of Michael Joseph Jandebeur to meet and post comments. Details of the annual family reunion can be found here.
- http://www.jandebeur.com

Jacomb
- Encompasses all permutations of the name including Jacomb, Jacombs, Jacombe, Jacom and Jacomb-Hood.
- http://www.jacomb.com/

Jonas-Knight-Grimshaw
- Ancestral database as compiled by Denise Jonas.
- http://worldconnect.rootsweb.com/cgi-bin/igm.cgi?db=:351478

Jess Family Tree
- Family database as compiled by Thomas Jess.
- http://worldconnect.rootsweb.com/cgi-bin/igm.cgi?db=:2090673

Jordanas
- Origin of the family name and Spainish connections. Features the descendants of Jose Jordana Font and Ana Centenera. Areas covered include Spain, the Philippines, Australia and the USA.
- http://www.jordanas.net/

Jaccard-Wolfgram and Families
- Family history as compiled by Cheryl Jaccard Cowart. Includes database, gallery, notices, reunions, guestbook and associated links.
- http://jaccard-wolfgram.org/

Jenkyn
- Family tree including the surnames Bartel, Batle, Cawthern, Cauthern and Williams.
- http://familytreemaker.genealogy.com/users/j/e/n/Thomas-Jenkyn

Jarrell
- Ancestors of Don Jarrell including surnames Burton, Westell, Waistell, McKay and Finlayson.
- http://www.jarrell.ca/

Jahnke Family
- Ancestral tree, photograph album, recipes and projects of Greg, Andi and Thomas Jahnke.
- http://www.jahnkefamily.com/

Janson Family
- Ancestors and decendents of Martin Janson. Surnames include Bonar, Backscheider, Dexter, Grebner, Strassel, Megel, Fegele and Simon.
- http://www.jansonfamily.com/

Jorgenson
- Family history of Conrad M Jorgenson from Sortland, Norway who settled in the Great Falls Montana area in 1907. Compiled by Gary Steven Jorgenson.
- http://www.conradjorgenson.com/

Jumper Family History
- Ancestral heritage of Samuel Jumper as compiled by Sherry A Jumper. Includes pedigree tree, photographs and associated lineages.
- http://www.samjumper.com/sherry/

Johns
- Family tree including Bush, Alden, Stockwell and Stebbins.
- http://www.gizmology.net/genealogy/

Janvrin
- Family history of Lance K Janvrin Snr, Lynn, MA USA.
- http://members.bellatlantic.net/~ljanvrin/

Jowers
- Family history of Carl and Myra Jowers including surnames Barlow, Harden, Lankford Bane, Barco, Cozene and Lee.
- http://www.100megsfree3.com/carljowers/