Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2023	Aug. 07, 2023
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q1
Trading Symbol	MNOV
Entity Registrant Name	MEDICINOVA, INC.
Entity Central Index Key	0001226616
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		49,046,246
Entity Shell Company	false
Entity File Number	001-33185
Entity Tax Identification Number	33-0927979
Entity Address, Address Line One	4275 Executive Square
Entity Address, Address Line Two	Suite 300
Entity Address, City or Town	La Jolla
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92037
City Area Code	858
Local Phone Number	373-1500
Entity Current Reporting Status	Yes
Document Quarterly Report	true
Document Transition Report	false
Entity Incorporation, State or Country Code	DE
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Stock, $0.001 par value
Security Exchange Name	NASDAQ