The Cooch Behar State was one of the mighty indigenous of India. The state had immense importance in ancient and medieval history of India. The Maharaja of Cooch Behar ruled the state for hundred years. The former Cooch Behar State has become a district of West Bengal since 1950. Maharaja BiswaSingha was the founder of the Cooch dynasty in Cooch Behar. After the death of Maharaja BiswaSingha, his son and successor Naranarayan ascended on the throne of Cooch Behat State in 1555 A.D. It became a vast empire during the reign of Maharaja Naranarayan. He was the most powerful king among all other kings of Cooch Behar State.The introduction of ?Narayani Coin? is one of the most important achievement of Maharaja Naranarayan which carries the identity of his sovereignty. It is unknown whether Maharaja BiswaSingha introduced coin in his name. No coin of Maharaja BiswaSingha has been discovered till date. The coin of the Cooch Behar State was first introduced in 1555 at the time of coronation of Maharaja Naranarayan.The coin is known as ?NarayaniCoin?.Two types of coin, gold and silver, named after Maharaja Naranarayan were made.On the one side the name of the Devanagari character Mahadev was printed and the name of the king was printed on the other side. Narayani coins were prevailing in some other neighboring states including Cooch Behar and Assam. In the past,trade routes extenden from Magadha to China?s Yunan through Assam.At that time the Narayani coin was the medium of trade in Jaintia, Khasi, Kachher, Manipur, Tripura with North East Asia. From the wide spread expansion of Narayani coin, it is understood that there was a great deal of trade and commerce in the state of Cooch Behar. In 1866, the British government of India stopped the circulation of Narayani coin. However, later on, the Maharaja of Cooch Behar used to prepare coin as a commemorative coin for the first day of ascendency.