Document and Entity Information	Feb. 14, 2024
Prospectus:
Document Type	497
Document Period End Date	Feb. 14, 2024
Entity Registrant Name	OBERWEIS FUNDS
Entity Central Index Key	0000803020
Entity Inv Company Type	N-1A
Amendment Flag	false
Document Creation Date	Feb. 14, 2024
Document Effective Date	Feb. 14, 2024
Prospectus Date	May 01, 2023
Oberweis Micro-Cap Fund \| Investor Class
Prospectus:
Trading Symbol	OBMCX
Oberweis Micro-Cap Fund \| Institutional Class
Prospectus:
Trading Symbol	OMCIX
Oberweis Small-Cap Opportunities Fund \| Investor Class
Prospectus:
Trading Symbol	OBSOX
Oberweis Small-Cap Opportunities Fund \| Institutional Class
Prospectus:
Trading Symbol	OBSIX
Oberweis Global Opportunities Fund \| Investor Class
Prospectus:
Trading Symbol	OBEGX
Oberweis Global Opportunities Fund \| Institutional Class
Prospectus:
Trading Symbol	OBGIX

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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