Chanakya's death is clouded with mystery and is not revealed exactly so far despite several efforts by scholars. However, there are two standpoints to it with the one stating that he starved himself to death and the other stating that he was killed through a clever plot woven around him. However, both these stand points stem from the story that is connected to his miserable fate.
Chanakya picked up Chandra Gupta from the streets and made him the ruler of a great empire in order to avenge the humility he suffered in the court of Nandas. Chandra Gupta Maurya proved to be a great emperor and nation builder under the able guidance of Chanakya. Chandra Gupta's son Bindusara succeeded Chandra Gupta in the throne and Chandra Gupta took to ascetic life during his last days.
Chanakya continued to be the chief advisor for Bindusara. Unable to tolerate the rapport that Chanakya enjoyed with Bindusara, a terrible plot was constructed to create enmity between him and the ruler. The master mind behind this plot was Subandhu, the minister of Bindusara. Subandhu made Bindusara believe that it was Chanakya who killed his mother in a treacherous manner. This created a severe contempt in Bindusara for Chanakya.
Chanakya was unable to put up with the behaviour of Bindusara whom he loved the most. Therefore, he left the palace and sat starving until death. During this time, a nurse who was with Bindusara's mother Dhurdha, revealed the mystery behind the queen's death relieving Chanakya from the guilt.
The story went this way. When Chandra Gupta, Bindusara's father was on the throne, Chanakya was adding poison to his food day by day to make him strong and immune even to the worst poison so that he shall not be poisoned by his enemies or conspirators. Not knowing this, the queen partook the food reserved for Chandra Gupta when she was pregnant.
Learning this, Chanakya wanted to save the heir to the throne and therefore cut open the womb of the mother to save the baby who was rescued from poison and named as Bindusara. In this process the queen succumbed to death. Ultimately, this act of Chanakya followed his duty towards the empire and as a measure to save Bindusara, who was to be the king of the empire.
Once Bindusara learnt this story from the nurse, he realized the grave mistake he committed by misunderstanding Chanakya. However, despite his efforts to pacify him and bring him back to the court, Chanakya refused to do so and continued to starve until death. Yet another version of the story states that Subandhu later cleverly burnt him alive. It appears that Bindusara killed Subandhu in utter disgust due to his evil plan. However, the mysterious death of Chanakya is not fully resolved yet.