Quarterly report pursuant to Section 13 or 15(d)


Cover - shares
6 Months Ended
Jun. 30, 2021
Aug. 10, 2021
Document Information [Line Items]    
Document Type 10-Q  
Amendment Flag false  
Document Quarterly Report true  
Document Transition Report false  
Document Period End Date Jun. 30, 2021  
Document Fiscal Period Focus Q2  
Document Fiscal Year Focus 2021  
Current Fiscal Year End Date --12-31  
Entity File Number 001-38325  
Entity Registrant Name Hancock Jaffe Laboratories, Inc.  
Entity Central Index Key 0001661053  
Entity Tax Identification Number 33-0936180  
Entity Incorporation, State or Country Code DE  
Entity Address, Address Line One 70 Doppler  
Entity Address, City or Town Irvine  
Entity Address, State or Province CA  
Entity Address, Postal Zip Code 92618  
City Area Code (949)  
Local Phone Number 261-2900  
Title of 12(b) Security Common Stock, $0.00001 par value  
Trading Symbol HJLI  
Security Exchange Name NASDAQ  
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 true  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   8,513,662
Warrant [Member]    
Document Information [Line Items]    
Title of 12(b) Security Warrant to Purchase Commons Stock  
Trading Symbol HJLW  
Security Exchange Name NASDAQ