Note 9 - Convertible Notes - Related Party - Convertible Notes Payable to Related Parties (Details) - Convertible Debt Payable to Related Party [Member] - USD ($)	Jun. 30, 2020	Dec. 31, 2019
Long-term Debt	$ 2,558,681	$ 2,558,681
Less: current portion	2,558,681	2,538,681
Long-term portion loans payable - related party		20,000
Bill Chaaban, President of Cen Biotech [Member]
Long-term Debt	1,388,122	1,388,122
Director, Harold Aubrey de Lavenu [Member]
Long-term Debt	878,368	878,368
Director, Alex Tarrabain [Member]
Long-term Debt	48,000	48,000
Joseph Byrne [Member]
Long-term Debt	224,191	224,191
Brother of Director Ameen Ferris [Member]
Long-term Debt	$ 20,000	$ 20,000

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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