The sum of the deal was not disclosed.
The Olympics will be broadcast on the public LTV1 and LTV7 channels.
"Neither Lithuania's, nor Estonia's public media have secured the rights to broadcast the Olympics, which will be broadcast by commercial channels either partly or in full. The situation is similar in Germany," said LTV's Sports Department head Andris Ušackis.
The Olympics will also be streamed online on lsm.lv and LTV's website ltv.lv.
"We're happy that we'll be able to [broadcast] the 2018 and 2020 Olympics as well. We are glad to be the Olympic television and we'll take sheer pleasure in boosting the 'Yes, Latvia can!' feeling," said LTV board chairman Ivars Belte.
Previously ERR, Estonia's public broadcaster, chose not to buy the rights to broadcast the 2018 and 2020 Olympics due to high fees. ERR was offered to pay €800,000 for the broadcasting rights.