The cute Panda cub named P, weighed less than 6oz when born, but is now he's a healthy 5.5lb.
The zoo has hosted six-year-old Hao Hao and her mate Xing Hui for the past two years under a deal with China.
Pairi Daiza worked with experts from China to artificially inseminate Hao Hao. edit.
It is an important step in the survival of the endangered species that numbers fewer than 2,000 worldwide.
Pandas are known for their struggle to reproduce but Belgium is the third country in Europe to see the birth of a cub, after Austria and Spain.
And conservation work is paying off. A World Wildlife Fund survey found there are almost twice as many pandas living wild now than there were in the late 1970s.