Sri Yukteswar was born Priyanath Karar in Serampore, India to Kshetranath Karar and Kadambini. Priyanath lost his father at a young age, and took on much of the responsibility for managing his family's land holdings.
A bright student, he passed the entrance exams and enrolled in Srirampur Christian Missionary College, where he developed an interest in the Bible. This interest would later express itself in his book, The Holy Science, which discusses the unity behind the scientific principles underlying Yoga and the Bible.
He also attended Calcutta Medical College for almost two years.
After leaving college, Priyanath married and had a daughter. His wife died a few years after their marriage, and he eventually was formally intitiated into the monastic Swami order as "Sriyukteshvar Giri" (note: thus 'Sri' is not a separate honorific, but part of his given name).

In 1884, Priyanath met Lahiri Mahasaya, who became his Guru and initiated him into the path of Kriya Yoga. Sri Yukteswar spent a great deal of time in the next several years in the company of his guru, often visiting Lahiri Mahasaya in Benares.
In 1894, while attending the Kumbha Mela in Allahabad, he met the Guru of Lahiri Mahasaya, Mahavatar Babaji, who asked Sri Yukteswar to write a book comparing Hindu scriptures and the Christian bible.
Mahavatar Babaji also bestowed on Sri Yukteswar the title of 'Swami' at that meeting. Sri Yukteswar completed the requested book in 1894, naming it Kaivalya Darsanam, or The Holy Science.

Spiritual Life
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Sri Yukteswar converted his large two-story family home in Serampore into an ashram, named "Priyadham", where he resided with students and disciples. In 1903, he also established an ashram in the sea-side town of Puri, naming it "Kararashram". From these two ashrams, Sri Yukteswar taught students, and began an organization named "Sadhu Sabha".
An interest in education resulted in Sri Yukteswar developing a syllabus for schools, on the subjects of physics, physiology, geography, astronomy, and astrology He also wrote a book for Bengalis on learning basic English and Hindi called "First Book", and wrote a basic book on astrology. Later, he became interested in the education of women, which was uncommon in Bengal at that time.

Sri Yukteswar was especially skilled in Vedic Astrology, and prescribed various astrological gemstones and bangles to his students. He also studied astronomy and science, as evidenced in the formulation of his Yuga theory in The Holy Science.
He had only a few long-term disciples, but in 1910, the young Mukunda Lal Ghosh would become Sri Yukteswar’s most well known disciple, eventually spreading the teachings of Kriya Yoga throughout the world as Paramahansa Yogananda. Yogananda attributed Sri Yukteswar’s small number of disciples to his strict training methods, which Yogananda said “cannot be described as other than drastic”.

Regarding the role of the Guru, Sri Yukteswar said:
Look, there is no point in blindly believing that after I touch you, you will be saved, or that a chariot from heaven will be waiting for you. Because of the guru's attainment, the sanctifying touch becomes a helper in the blossoming of Knowledge, and being respectful towards having acquired this blessing, you must yourself become a sage, and proceed on the path to elevate your Soul by applying the techniques of sadhana given by the guru. It is in the path of meditation, truthfulness, and surrendering to God that the Guru-graced sadhaka becomes successful in attaining revelation and understanding of new methods of learning.

Author W.Y. Evans-Wentz describing his impression of Sri Yukteswar in the preface to Yogananda's Autobiography of a Yogi. said;
"Sri Yukteswar was of gentle mien and voice, of pleasing presence, and worthy of the veneration, which his followers spontaneously accorded to him. Every person who knew him, whether of his own community or not, held him in the highest esteem. I vividly recall his tall, straight, ascetic figure, garbed in the saffron-colored garb of one who has renounced worldly quests, as he stood at the entrance of the hermitage to give me welcome. His hair was long and somewhat curly, and his face bearded. His body was muscularly firm, but slender and well-formed, and his step energetic."

Sri Yukteswar died at his Puri ashram on March 9, 1936.