Mahesh (Mehmood) is a poor rickshaw puller. One day, he goes to temple and sees a child lying on the stairs. He takes him inside the temple to give him to his parents but the priest assuming that the child is his sin, asks him to get out of the temple. Police constable also helps the priest and asks Mahesh to take his child along with him. Mahesh tells them that it is not his child but they do not listen. Then Mahesh tries to leave the child but fate lets him take the child home.
There also, he faces opposition from the neighborhood due to the child but irrespective of their behavior, Mahesh starts bringing up the child and names him 'Hindustan'. On the other hand, Radha (Bharathi), the child's mother attempts suicide because the child's father, Vinod (Vinod Mehra), refuses to marry her. So, unable to bear the burden of sin, she tries to commit suicide but is saved by the local people.
When she comes into conscious, she starts searching her child. She goes to police and also requests Vinod but Vinod rejects her cruelly. Vinod gets injured in an accident and is ashamed of his behavior. He apologizes to Radha and both of them get married. They along with Inspector Ramesh start finding their child. In bringing up the child, Sheela (Manorama), helps Mahesh.
One day Mahesh comes to know that Hindustan has got infected with polio. He, feeling responsible for Hindustan's disease because of his uncleanliness, works hard to give the child a good education. Will he succeed in achieving his goal and will Radha be able to find her child?