City of Wolverhampton College student Devon Beckett, from Bushbury, snapped the colour image of his cat, Belle, in his garden.
He was encouraged by his tutor to enter the competition, organised by the gallery to coincide with its current Wildlife Photographer of the Year exhibition.
The 16-year-old, who is studying for a two-year UAL level three extended diploma in photography, said: "I only entered the competition for fun, so to win was a bonus and is a great achievement for me.
"I knew the basics of photography before I started the course, but this has taught me much more, encouraged me to try new techniques and helped me be more selective with my pictures.
"I love photography and want to have my own business in the future."
Chris Hill, photography tutor at the college, said: "Devon only started his qualification at the college in September but has shown a real aptitude for photography and a commitment to learning and using the skills he's gaining to improve even further."
Devon also entered a second image – of a bee collecting nectar from a flower – in the competition and both are on display at the art gallery until December 24.
For details of photography courses offered by the college go to wolvcoll.ac.uk/demographic/school-leavers/category/creative-arts-courses