Wife: Ruth Martin
Children: Tara Martin (with Helen Martin), Jeff Martin (with Helen Martin), Jake Martin (with Ruth Martin), Tad Martin (adoptive)
Grandchildren: Jamie Martin (adoptive), Kelsey Jefferson, Charlie Brent
Great-Grandchildren: Sam Grey (adopted by Edmund and Maria Grey)
Mother: Kate Martin (deceased)
Siblings: Paul Martin
Niece: Beth Martin (deceased)
Sister-in-law: Amy Tyler
Significant Romantic Relationships: Helen Martin (1st wife/deceased), Ruth Martin (2nd wife)

Joe Martin has been a strong presence in Pine Valley since All My Children's first episode. Joe, a widower with two children-Tara and Jeff -moved to Pine Valley after the death of his wife. Joe, Tara and Jeff lived with Joe's mother Kate, while Joe went to work at Pine Valley's hospital. It was there he met Ruth Brent, a kind nurse with whom he felt an immediate connection. Under normal circumstances, Joe and Ruth might have started dating, but Ruth was married to alcoholic Ted Brent. Joe and Ruth developed a strong friendship, with Joe often being a shoulder to cry on during Ruth's problems with Ted. Ted eventually was killed in an accident and Joe and Ruth moved into a romance. They got engaged and eventually married.

After his son Jeff left town, Joe and Ruth took in young Tad Gardner, whom Jeff had been looking after. They wanted to adopt Tad, but could not do so until his biological parents were found. Joe's daughter, Tara and Ruth's adopted son, Phil, were having romantic troubles of their own which Joe and Ruth often got involved in. Ruth wanted Tara and Phil to reunite, whereas Joe felt it wasn't their place to interfere. Complications and misunderstandings ensued, and Joe and Ruth briefly separated over their difference in opinion about their children's lives. Ruth was briefly tempted by handsome Dr. David Thornton, but their love was too strong and they reunited.

Ray Gardner, Tad's biological father, was located and Joe visited him in an effort to legally adopt Tad. Ray demanded $10,000 in exchange for signing over parental rights to Tad, but Joe refused on principle. An angry Ray traveled to Pine Valley where he caused a reign of terror that culminated in his rape of Ruth Martin. Joe supported Ruth in the trying time afterwards, including her testimony against Ray. Ray was sent to prison and Joe and Ruth were free to adopt Tad. Another addition to the Martin family arrived when Joey (now called Jake), Ruth and Joe's son, was born.

Joe treated an abused wife, Leora Sanders, at the hospital and grew very close to her. Ruth and Joe separated over Joe's closeness to Leora, but reconciled when they realized how much they loved each other.

After Charles Tyler's death in 1986, Joe became the new chief of staff of Pine Valley. In 1997, during an argument with Dimitri Marick, Joe suffered a near fatal heart attack. Thankfully, he fully recovered.

Joe, along with wife Ruth, have remained pillars of the Pine Valley community. Happily married for over thirty years, Joe has always been a reliable source for sound advice and friendly comfort.