The aim of the article is an effort to capture the history of insulin production in Czechoslovakia. Information has been obtained mainly from two Czech journals: "Časopis lékařů českých" (published since 1862) and "Praktický lékař" (published since 1921). At first, imported insulin in the form of insulin injections or substances from which insulin was prepared appeared at the market in Czechoslovakia. During years 1923-1945, insulin was produced by five companies, since 1945 only by one company "Léčiva".
Keywords: diabetes mellitus - insulin - production of insulin..