The 36-year-old Frenchman was impassive as the verdict was read out. He turned to look at members of his own family who were present.
Earlier, he had said “Sorry, Sorry” in the dock, looking towards his wife's parents.
Daval finally confessed to beating his wife to death and burning her body in the woods after initially reporting her missing.
The charred remains of Alexia Daval were found hidden under branches near their town of Gray-la-Ville in eastern France in October 2017.
Daval initially said Alexia, a 29-year-old bank employee, had gone jogging and never came back.
Jean-Pierre Fouillot, Alexia's father, passed an arm around the shoulders of his wife Isabelle as the court's decision was delivered.
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A few minutes later the mother, Isabelle Fouillot, went out to talk to reporters, as she had done throughout the trial.
“It is a very good decision, exactly what I hoped, at the height of our suffering. That will allow us to turn a page,” she said.
'Almost perfect conjugal crime'
Defence lawyer Ornella Spatafora swiftly indicated that there would be no appeal against the sentence.
Outside the courthouse dozens of people were pressed against the barriers blocking access to it.
Prosecutors had asked for a life sentence calling the 2017 murder “an almost perfect conjugal crime.”
After his wife's death, Duval had cut a distraught figure, appearing in tears at a press conference with his in-laws and leading one of several events organised countrywide in her memory.
Three months later, prosecutors said the IT worker confessed to the murder – admitting he had beaten his wife in a heated argument, knocking her face against a concrete wall, and strangling her.
He initially denied setting fire to her body, but finally admitted to that too, in June last year.
Daval changed his story several times, at one point withdrawing his confession, blaming his brother-in-law, and finally admitting to everything all over again.
On Monday, when asked by the judge whether he admitted to “being the only person implicated in the death” of his wife, Daval replied “yes”, appearing close to tears.
The crime deeply shocked France, and nearly 10,000 people turned out in the couple's quiet town for a silent march in her memory.
The murder highlighted the scourge of violence against women at the height of the global #MeToo campaign against sexual abuse and harassment of women.
On Monday, French authorities said 125,840 women were victims of domestic violence in 2019. Another 146 were murdered by their partner or ex-partner – 25 more than the previous year.