According to China University of Hong Kong, most Chinese boys weigh around 18 pounds at that age.
His mother told the paper that he has a "ravenous" appetite.
Experts say that if he continues to eat that way, he's at risk for serious health problems, even at a young age.
"When kids are overweight at any age, they're much more at risk for diabetes," said Keith Ayoob, associate clinical professor of medicine at Albert Einstein College of Medicine in New York.
The Daily Mail says that Lei Lei is at a hospital in China undergoing tests to find out if there's a medical reason for his weight gain.
Ayoob said that there are medical conditions that can cause children to become extremely overweight, such as Prader-Willi Syndrome or hormonal imbalances.
But he also said children -- even very young ones -- often become overweight because their parents simply feed them too much.
It can happen when mothers are constantly bottle feeding of if they start solid foods too soon," he said. "They think that every time the child cries, the baby is hungry."
Lei Lei isn't the only child whose weight has attracted recent attention. And with it comes a second question: Can obesity in young children be a sign of parental abuse?
A couple from Marietta, Georgia was arrested Thursday and charged with felony child cruelty after police found their two daughters, ages 5 and 4, living in extremely squalid conditions.
According to the arrest warrants for James and Anne Cardona, the children are also extremely overweight. The 5-year-old weighs 158 pounds and cannot walk more than a few feet without losing her breath, and the younger child weighs 89 pounds. Information from the Centers for Disease Control and Prevention shows that girls around age four generally weigh around 35 pounds, and 5-year-old girls weigh around 40 pounds.
A neighbor told ABC affiliate WSB-TV that the children are definitely obese and probably have health problems. Anne Cardona told WSB that her children were not abused, but that there were "issues." She declined to go into specifics.
Although the Cardonas' children and Lei Lei are all extremely overweight, experts say that does not in itself constitute abuse, despite the public's perception that it does.
Linda Spears, vice president of policy and public affairs at the Child Welfare League of America said the issue of abuse is raised when cases involving obese children removed from their homes come into the public eye.
"Obesity is usually part of a much bigger problem. In a child protective services capacity, it would be seen as medical neglect, and that's just part of the whole picture," Spears said.
"There are often a lot of things going on," she added. "The question is what's going on with the family that's causing the situation in which you have an obese child with health consequences that are not being addressed."
"It's potentially giving your child a medical problem," said Ayoob. "Not doing anything about it is a more serious charge." He stopped short of calling it abuse, however.
Social service departments could see more cases involving child obesity as the epidemic across the nation continues to grow.
"There's a good likelihood that you will see a larger percentage of these cases becoming part of the child welfare caseload," said Spears.