Melissa Hoskins, an Olympic track cyclist and former world champion, died after being struck by a car driven by Dennis in an inner northern suburb of Adelaide in 2023.
The court had heard how she held on to the car as he attempted to drive off following an argument, causing her to fall.
Dennis had admitted to an aggravated count of creating the likelihood of harm, and the judge said that although he had disregarded his wife's safety he was not criminally responsible for her death.
He was sentenced to one year, four months and 28 days in jail, suspended for two years, and his driver's licence was suspended for five years.
In a statement on social media, Dennis said he loved his wife and never intended to hurt her.
"The narrative which the media ran with was clear. They wanted me to look like the husband who abused his wife," the 35-year-old said.
"The media speak about the children and how saddened they are for the children. Yet they happily stalk, follow and harass not just adults in my family but even when the kids are involved.
"They know I never intentionally or unintentionally used a vehicle as a weapon... Time for all you so called journalists and media outlets to back off and leave my family alone."
In addition to two time trial world titles, Dennis won team pursuit silver at the 2012 Olympics and a time trial bronze at the Tokyo Games.
Hoskins won team pursuit gold at the 2015 world championships and was on the Australian team at the 2012 and 2016 Olympics.
