Liu held a lead during the whole course and finished the race with 1 hour 27 minutes and 45 seconds. She was followed by another Chinese Lv Xiuzhi who won the silver medal.
The Chinese duo has taken an early lead and passed the 5km point in 22:24.
Liu feels happy about the result.
"First of all, I am very happy and I have achieved one of my dreams. I competed the 2008 Olympics here and ranked in fourth place. Coming back here today to compete and walking in the Birds' Nest to finish first, I am very thrilled, this is a big honour and I am really happy."
However, her compatriot Lv Xiuzhi suggests they could have done a better job.
"Our timing today was not very good, as our best times are both an hour and 25 minutes. Although we are not satisfied with our timing, we are happy that the gold and silver both went to China. We didn't think too much about the requirement of timing or speed."
As a veteran race walker, Liu has won two bronze and one silver medal at the previous four championships.
She holds the world record at one hour, 24 minutes and 38 seconds, setting that mark in June.
She says winning the gold has long been on her mind.
"Before the competition, I had thought a lot about winning the gold, walking into the stadium in first place and stepping up to the podium. However, when it comes true, the feeling is quite different."
Lyudmyla Olyanovska of Ukraine has taken home the bronze medal, 28 seconds behind Liu.
Another Chinese walker, Nie Jingjing, has clocked 1:32:40 for 17th.
For CRI, I'm Qian Shanming.
