Tri, 49, replaces Mai Duy Long, also 49, who helmed AVG for nearly two years.
Tri, who became the CEO of Sony Ericsson Vietnam in 2006, has since taking top positions in the Vietnam operations of Yahoo, Qualcomm and Microsoft.
He is now the CEO of telecom firm Asim Group and two other companies.
State-owned MobiFone, the country's third largest telecommunications firm, had made headlines early in 2016 when it announced it was breaking into the pay TV market with the acquisition of a 95 percent stake in AVG.
But government inspectors concluded that the deal had violated public investment laws and caused an estimated loss of about VND7 trillion ($307 million) to the state budget.
In 2019, several senior officials implicated in the MobiFone case were arrested and sentenced to varying jail terms.