Oktay Güvemli was born in a town (Fatsa – the district of Ordu, Turkey) on the coast of Eastern Black Sea. He completed his undergraduate education at the Academy of Economics and Commercial Sciences, in Ankara, 1960. He finished his master degree in Istanbul University, 1961. Between 1963 and 1973, he worked as an analyst financier at the Industrial Investment and Credit Bank (Sınai Yatırım ve Kredi Bankası). He began his academic life at Marmara University in 1973. He became Associate Professor in 1974 and Professor in 1980. Prof. Güvemli has been continuing his academic life along with CPA career in the private sector.

He received education in Belgium and France in 1967 during the development stage of European Economic Community. He worked as an intern at the European Investment Bank. His first international accounting activity was the World Accountants Congress of Paris, 1967.

He established the Association of Accounting and Finance Academicians of Turkey (MUFAD) in 1990s and acted as its chairman for years. This association organized the 12th World Congress of Accounting Historians in Istanbul, 2008. This association also organized conference series titled Balkans and Middle Eastern Countries Accounting and Accounting History Conferences in 2007, 2010 and 2013, in Edirne and Istanbul.
During his academic life between 1973 and 1990, he gave lectures and wrote books about Financial Statements Analysis, Preparation and Evaluation of Investment Projects and Corporate Planning.

He pursued interest towards accounting history around 1990s. In 1994, he translated and published the Pacioli’s Summa in Turkish. Afterwards, he completed his four series work titled Accounting History of Turkish States within six years. He participated at the 8th World Congress of Accounting Historians (WCAH) in Madrid, 2000. He organized a Turkish delegation to attend the 2004 (St. Louis) and 2006 (Nantes) Congresses with papers. He was the convener of the 2008 Istanbul Congress where 55 different countries participated and 240 papers submitted. Once again, he organized a Turkish delegation to participate at the 13th WCAH in Newcastle, 2012 with 19 papers. Today, he is working to organize a delegation of Turkish academicians to participate at the 14th WCAH in Pescara, Italy (June, 2016).

Oktay Güvemli aimed to establish relations with the academicians of Balkans and Middle Eastern countries between the years 2000 and 2013 in order to increase accounting history activities. He visited Egypt, Iran, Greece, Macedonia, Romania, and Albania many times in order to exhibit the five thousand years of recording culture of Middle East. He wrote books about this subject along with fellow academicians and participated at international conferences. He also published the Conference Proceedings of the mentioned activities in 2007, 2008, 2010 and 2013.

He focused his researches towards the Islamic Era (622-1850) and westernization era (1850-2011) of Middle Eastern recording culture. Recently, he published a book regarding this subject along with Prof. Cengiz Toraman and Prof. Batuhan Güvemli, titled State Accounting in the Ottoman Empire – Anatolian Accounting Culture in 2015. In 2019, he contributed to the publication of a three volume encyclopedia titled History of Middle East Accounting (3000 BC - 2000 AD) along with fifteen academicians.

Prof. Güvemli was the editor of Accounting and Financial History Research Journal, which is published semi-annually in Turkey. He assisted the preparation of a monthly program about accounting history in a local TV channel. He was also the chairman of board of trustees at the Oktay Güvemli Waqf of Accounting and Financial History (MUFTAV). This waqf serves accounting history community with its one of the biggest accounting libraries in the Balkans and Middle East. The library is located in Istanbul with its fifteen thousand (in ten languages) accounting, finance and accounting - financial history books.

Prof. Güvemli was married, and had three children and six grandchildren.