Six suspects involved in the human trafficking case have been arrested, Xinhua reported.
The baby was recovered in Anyang city of central Henan province Sunday, but DNA tests must be conducted to confirm its identity, officials said. The baby was in good condition.
The baby boy was allegedly sold for 21,600 yuan (around $3,500) by an obstetrician from Fuping County Maternal and Child Health Care Hospital a day after he was born July 16, officials said.
The doctor, surnamed Zhang, has been detained on suspicions of human trafficking, police said.
They said Zhang allegedly obtained the baby by falsely claiming that the child had congenital diseases, and convincing the mother to abandon treatment and allow the doctor to handle the baby.
The mother later realised that her baby might have been abducted and reported the case to police.
Two people from Shanxi province who purchased the baby from Zhang have also been detained. They later sold the baby for 30,000 yuan, police said.
The hospital's head and her two deputies were sacked Sunday over the trafficking case.
Police said they were also investigating five other similar cases which allegedly occurred in the same hospital.