In June 1841, Nikolopoulos dies suddenly in Paris. The books he so loved seem to have led him to an early end. According to one version, he died of poisoning, due to the dust he inhaled while cleaning his books. However, the second and most widely accepted, states that while shaking the dust off the books, which he placed in chests to protect during transportation to Greece, he scraped his hand. The wound was deep and quickly became infected, so he ran a fever and died a few days later at the Hotel Dieu Hospital in Paris, from tetanus.