The Kan'ei Tsūhō (Kyūjitai: 寛永通寳; Shinjitai: 寛永通宝) was a Japanese mon coin in use from 1626 until 1868 during the Edo period.

These beneficial circumstances in the economy boosted trade which raised the demand for money by merchants and other traders in order to keep the commerce growing, The alternate attendance system forced the daimyō to reside every other year in the Tokugawa capital of Edo and these daimyō would spend vast quantities of money there.

The original 1 mon Kan'ei Tsūhō was produced by the Mito domain in 1626 in minor quantities, this happened in response to the booming economy Japan had experienced to meet the demand for circulating copper coins.

Due to a shortage in copper from 1656 until 1660 only 300,000 Kan'ei Tsūhō cash coins were produced at Torigoe in Edo and 200,000 at Kutsunoya in Suruga.

[7] Copper mines began to run out in Japan during the early eighteenth century, which made the metal more scarce causing its value to increase.

This in turn caused the price to manufacture cash to increase, and eventually the nominal value of the coins became lower than their intrinsic value.

As the economy was still growing the Japanese population accepted these coins at their face value because of the strong demand for (circulating) currency.

Another type of 4 mon Kan'ei Tsūhō coins are the Ansei Kan'ei produced during the Ansei era (1854–1859), these coins to be more yellowish due to the fact that they were made from brass as opposed to bronze and gave rough faces while they have very clear file marks.

Concurrently as the government of the Tokugawa shogunate started to allow local domains to issue their own 4 mon Kan'ei Tsūhō coins they themselves started minting the Bunkyū Eihō (文久永宝) cash coin from 1863, the inscription on the coin refers to the Bunkyū era (1861–1864), Eihō (永宝) could be translated as "eternally circulating treasure" indicating a very hopeful name for the new series which did not come into fruition as the Japanese mon was superseded by the yen during the Meiji restoration.