Erol Denec was born in Istanbul. He studied arts at the academy of Applied Fine Arts in Istanbul in early 1960s. During his study at the academy, in 1962, Denec met Anton Lehmden, an Austrian painter, whom later on changed the course of his artistic life. Lehmden was a co-founder, together with Ernst Fuchs, Rudolf Hausner, Arik Bauer and Wolfgang Hutter of the Vienna School of Fantastic Realism. Soon, due to his unmistakable talent, Denec was invited by Ernst Fuchs to Vienna in 1964 to study art at the academy of Fine Arts. Denec mastered the techniques of Fantastic Art during his stay at the academy between 1964 and 1973. During this period, he participated in many exhibitions of Fantastic Art throughout the European countries, mainly in Austria. In 1973, he suddenly decided to live in a more rural environment to be in direct contact with nature and began to live on a hill at the outskirts of Austrian Alps with his wife. He carried on with his artistic activities in his home studio and attended numerous Fantastic Art exhibitions.

In 1989, he returned to his home city, Istanbul and began to teach art to young students at the Istanbul University Cultural Centre and formed IFAR Art Group to institutionalize the Fantastic Art in Turkey. He is the pioneer of Fantastic Art in Turkey.

He has been residing in Istanbul since 1989 and carrying on with his art and teaching. He is still very active and attends many exhibitions. His artwork has been acquired for by many public institutions and private collections.