Guru Har Krishan (Punjabi: ਗੁਰੂ ਹਰਿ ਕ੍ਰਿਸ਼ਨ) (7 July 1656 – 30 March 1664) was the eighth of the Eleven Gurus of Sikhism. He became Guru on 7 October 1661, succeeding his father, Guru Har Rai. Before Guru Har Krishan died, he nominated his granduncle, Guru Teg Bahadur, as the next Guru of the Sikhs.

Guru Har Krishan was born in Rupnagar, Punjab, India to Guru Har Rai and Kishan Kaur (Mata Sulakhni). Before his death in October 1661, Har Rai designated his younger son Har Krishan as the next Guru. Har Rai chose Har Krishan, rather than his elder son Ram Rai, because Ram Rai was in collusion with the Mughal Empire. Har Krishan was only five years old when he succeeded his father as Guru.

Ram Rai complained to the Mughal emperor Aurangzeb in Delhi that he had been passed over because of his loyalty to the emperor. He also claimed that he had not received his due share of his father's property. Ram Rai knew that before his death Har Rai had publicly instructed Har Krishan never to meet Aurengzeb. Ram Rai hoped if Har Krishan met the emperor, it would be against his father's wishes and the Sikhs would be displeased with their Guru. On the other hand, if Aurangzeb summoned Har Krishan to Delhi, and he refused to go, then Aurangzeb would send troops to compel him. Aurangzeb favored Ram Rai, and summoned Har Krishan to Delhi. The Sikhs were very apprehensive about young Har Krishan travelling to Delhi and appearing at court. To calm these worries, Aurangzeb sent Raja Jai Singh to escort the Guru to Delhi. Raja Jai Singh was a high court official and also a Sikh known for his devotion to the Gurus.

Raja Jai Singh assured Har Krishan that he would not have to meet the emperor personally while in Delhi. He also said there were many devout Sikhs in Delhi who were anxious tHar Krishano see and hear their Guru. Har Krishan convinced the Sikhs at Kiratpur that he should go to Delhi. Har Krishan, his mother, and a group of devotees set out for the long journey to Delhi. On the journey, Har Krishan was met by large crowds of devotees.

At Panjolhara, a jealous Brahmin taunted the Guru, mangling his name, which was close to close to that of the Hindu god Krishna. The Brahmin said “Your Guru is called Hari Krishna, a mere child of eight years! Krishna, the incarnation of Vishnu, uttered the Gita, which is the repository of all the eternal truths. If your Guru also calls himself Krishna, let him expound the truths of Gita to us.” Hearing this, a poor water-carrier named Chhajju stood up, and proclaimed that anyone could expound on the Gita if he were so blessed by the Guru. Har Krishan touched Chhajju with his walking stick, and Chhajju immediately began to expound the philosophy of the Gita. The Brahmin was so humbled by the spectacle that he fell to Har Krishan's feet and asked forgiveness for his arrogance.

When they reached Delhi, Har Krishan and his party were the guests of Raja Jai Singh, who had promised to maintain Har Krishan's safety. Every day, large numbers of Sikh devotees flocked to see the Guru. A smallpox epidemic was then raging in Delhi. Har Krishan helped to heal many sick people. Coming in contact with so many people every day, he too was infected and taken seriously ill. On March 30, 1664, Har Krishan decided to name his successor. He called for five coins and a coconut. He took them, and being too weak to move, waved his hand three times in the air, and said “Baba Bakala.” Har Krishan then suddenly passed away at the tender age of eight years old.