Annual report pursuant to Section 13 and 15(d)


Cover - USD ($)
12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Apr. 10, 2024
Jun. 30, 2023
Cover [Abstract]        
Document Type 10-K      
Amendment Flag false      
Document Annual Report true      
Document Transition Report false      
Document Period End Date Dec. 31, 2023      
Document Fiscal Period Focus FY      
Document Fiscal Year Focus 2023      
Current Fiscal Year End Date --12-31      
Entity File Number 001-39555      
Entity Registrant Name GREENWICH LIFESCIENCES, INC.      
Entity Central Index Key 0001799788      
Entity Tax Identification Number 20-5473709      
Entity Incorporation, State or Country Code DE      
Entity Address, Address Line One 3992 Bluebonnet Dr.      
Entity Address, Address Line Two Building 14      
Entity Address, City or Town Stafford      
Entity Address, State or Province TX      
Entity Address, Postal Zip Code 77477      
City Area Code (832)      
Local Phone Number 819-3232      
Title of 12(b) Security Common Stock, $0.001 par value      
Trading Symbol GLSI      
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 Filer Category Non-accelerated Filer      
Entity Small Business true      
Entity Emerging Growth Company true      
Elected Not To Use the Extended Transition Period false      
Entity Shell Company false      
Entity Public Float       $ 56,572,305
Entity Common Stock, Shares Outstanding     12,878,409  
ICFR Auditor Attestation Flag false      
Document Financial Statement Error Correction [Flag] false      
Auditor Firm ID 587 206    
Auditor Name RBSM LLP MaloneBailey, LLP    
Auditor Location Austin, Texas Houston, Texas