He started painting when he was still working as a trained barber in Osijek. His work was then noticed by Andrija Krbavac, the local printing institute owner, who later became his patron and provided him with the necessary working space and tools. When Benkovic was still an amateur, Krbavac organized his first exhibition.

In 1948, he majored in painting and graphic art from the Zagreb Academy of Visual Arts. He was one among the best European calligraphers, also known as a long-standing alphabet professor at the Zagreb School of Applied Arts. His professional interests included the study and elaboration of alphabet, as well as finding methods for its application in a number of practical contemporary tasks. His educational activities resulted in the textbook entitled "Alphabet, History, Aesthetics, and Teaching Methods" 1, from 1963.

Apart from his teaching and painting, he was also engaged in calligraphy (medallions, degrees, citations), as well as in graphic design of books and posters. He assisted Ljubo Babic, another famous Croatian artist, in the making of a board for the 1937 World Expo in Paris. In 1939, he did the written part of the large board for the World Expo in New York.

The public interested in visual arts is not familiar enough with his work, including hundreds of sketches, drawings, and paintings. The most frequent topics of his painting were man and his homeland: The environment and people surrounding it. He was painting Slavonian and Mediterranean landscapes, numerous portraits and self-portraits, old people, Slavonian country women, reapers, children, interiors. His particularly favourite subjects were the nudes.