In this study, the reaction of the Ottoman Empire to the declaration of independence of Bulgaria, the first ambassador of the Ottoman Empire in Bulgaria, Mustafa Asım Bey and his activities are discussed. The study examines the diplomatic activities of the Ottoman Empire against Bulgaria in the period between the autonomy process of Bulgaria and the independence process, the process of recognition of Bulgaria’s independence, the diplomatic relations established with Bulgaria, the biography of Mustafa Asım Bey, the first Ambassador of the Ottoman Empire to Sofia, and his approach to the problems between the two countries. In the article, documents from the Ottoman Archive of Directorate of State Archives (BOA), documents from the Bulgarian State Archives, periodicals and literature were used.