The arrest occurred after the man's wife filed a complaint accusing him of the brutal murder.
The accused, identified as Sachin Bordoloi of Gohpur, is said to have left his home on Thursday with the infant but failed to return.
Later, the child's body was discovered in a paddy field.
Suspicions arose over Bordoloi's involvement in the crime as he was missing following the incident.
"After committing the crime, the accused left for Cementchapri and returned home at around 3 a.m. on Fridat. The victim's mother accused her husband of committing the crime. In response to her complaint, the police arrested him. So far, it has come to light that he committed the crime as a result of certain family conflicts," a senior police officer said.
According to police, a bicycle together with a shopping bag was also found near the scene of the murder in Gohpur.
Meanwhile, the locals have demanded stern action against the accused. Guwahati, March 10 (IANS)