Cover Page - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Mar. 30, 2022	Jun. 30, 2021
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2021
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-36856
Entity Registrant Name	HEPION PHARMACEUTICALS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	46-2783806
Entity Address, Address Line One	399 Thornall Street
Entity Address, Address Line Two	First Floor
Entity Address, City or Town	Edison
Entity Address, State or Province	NJ
Entity Address, Postal Zip Code	08837
City Area Code	732
Local Phone Number	902-4000
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Trading Symbol	HEPA
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Small Business	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Entity Shell Company	false
Entity Public Float			$ 150.8
Entity Common Stock, Shares Outstanding		76,229,571
Documents Incorporated by Reference	Parts of the registrant’s Proxy Statement for the Registrant’s 2022 Annual Meeting of Stockholders are incorporated by reference into Part III of this Annual Report on Form 10-K. Such Proxy Statement will be filed with the Securities and Exchange Commission within 120 days of the registrant's fiscal year ended December 31, 2021.
Entity Central Index Key	0001583771
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Filer Category	Non-accelerated Filer