The FIVB confirmed the men's and women's competitions would not take place as a result of the COVID-19 crisis.
Start dates for both tournaments, which had been scheduled to begin this month, were postponed by the FIVB in March, with a view to holding the events later this year.
Turin in Italy and Nanjing in China had been due to stage the men's and women's finals respectively and the FIVB said the two countries are set to be retained as host nations for the 2021 finals.
The Nations League, where teams play in a worldwide round-robin format before the top six progress to the finals, is the latest major volleyball event to be called off because of the COVID-19 pandemic.
FIVB President Ary Graça said it would have been "irresponsible" for the worldwide body and organisers to go ahead with the event amid the global health crisis.
The FIVB postponed the start date of the tournament in March in response to the COVID-19 pandemic ©Getty Images
"Together with our partners, we had explored all the various options to host the Volleyball Nations League 2020," Graça said.
"Part of what makes the event so special is that it is a truly global event enjoyed by players and specially by fans from all around the world.
"But this strength also increases its risk during this current global pandemic.
"It would therefore be imprudent, maybe even irresponsible for us to go ahead with the event when we cannot provide players and all stakeholders with the certainty that the Volleyball Nations League 2020 would be safe, accessible to all and held at a high level.
"Instead, our attention now turns to Volleyball Nations League 2021 and making sure it is our best ever edition.
"I know that our incredible athletes will be unrelenting in their efforts to prepare for the competition, and I have no doubt that next year will prove to be a very exciting year for volleyball."
According to latest figures, more than four million people have been infected and more than 276,000 have died from COVID-19.