The actor, 66, posted a sweet video to Instagram late Friday dancing with the couple's daughter, Ella, 20.
"My daughter @ella.travolta and I dancing in memory of momma. One of Kelly's favorite things, dancing with me," he captioned the clip.
In the video, the dad and daughter duo are seen dancing in a restaurant as the actor twirls Ella twice.
Preston, who starred in movies such as "Jerry Maguire" and "Twins," died in July at the age of 57 after battling breast cancer for two years. Her husband confirmed her passing on Instagram.
"It is with a very heavy heart that I inform you that my beautiful wife Kelly has lost her two-year battle with breast cancer," Travolta wrote on Instagram one day after her passing. "She fought a courageous fight with the love and support of so many. "
He continued: "My family and I will forever be grateful to her doctors and nurses at MD Anderson Cancer Center, all the medical centers that have helped, as well as her many friends and loved ones who have been by her side. Kelly’s love and life will always be remembered."
Travolta also asked for forgiveness if he steps out of the spotlight for a while, as he vowed to be "taking some time to be there for my children who have lost their mother."
Preston was born on Oct. 13, 1962, in Honolulu, Hawaii. She studied acting at the University of Southern California and went on to star in hit films such as 1988's "Twins," 1996's "Jerry Maguire" and 1999's "For Love of the Game."
Travolta and Preston met while filming 1989's “The Experts.” They married in 1991 at a midnight ceremony in Paris and had been together ever since. Her last movie role was portraying Victoria Gotti in the 2018 movie "Gotti." The movie also starred Travolta as John Gotti in the leading role.
A death certificate obtained by Us Weekly shows that Preston died in the family's Clearwater, Fla., home.
Preston is survived by her husband, 66, daughter Ella, 20, and 9-year-old son Benjamin. Their son Jett died in 2009 at the age of 16.