"The time has come," she wrote in a caption on Instagram, alongside a carousel of images from the evening. “The time is now. Welcome to the Fifa World Cup Qatar 2022."
The images show her with her husband, Sheikh Hamad, former emir of Qatar, and her children, Sheikha Hind bint Hamad and former heir apparent Sheikh Jassim bin Hamad.
She also posted a Reel with clips from the opening night, with the message: "Welcome, and good luck to all."
Sheikha Moza, who is also the co-founder and chairwoman of the Qatar Foundation, married Sheikh Hamad in 1977.
Sheikha Jawaher bint Hamad, Sheikh Tamim's first wife and consort, received the wives of world leaders from participating countries as the much-anticipated event began.
Sheikha Al-Mayassa bint Hamad, Sheikh Tamim's sister and Sheikha Moza's daughter, also posted a photo of the opening ceremony to Instagram, writing in the caption: "Tonight we celebrated the world through the power of football. I couldn’t be more proud of our leader, my brother — my whole family — the men and women who worked day and night for this moment.
"For 12 years Qatar was unfairly attacked — for some reason these critics believed that an Arab and Muslim nation was incompetent to organise such a tournament. Tonight we set the bar high, and La3eeb is ready to take you through a journey of a lifetime.
"We’re ready to welcome all those who are here, and those who will arrive in the coming weeks. Hard luck to Qatar and congrats to Ecuador."
Enner Valencia led Ecuador to victory in their opening match as the South Americans eased past Qatar.
Valencia scored both goals in the 2-0 win at Al Bayt Stadium to give Ecuador the ideal start in Group A.
Qatar manager Felix Sanchez conceded the weight of the occasion got to his players as they became the first host nation in World Cup history to suffer defeat in their opening game.
“There’s no excuse. We want to congratulate our opponents, they deserved to win,” Sanchez said.
Scroll through the gallery below to see more images of the opening ceremony