Nikša Antonini was born on 23 May 1956 in Makarska. His interest in photography began in secondary school and gradually developed into an absorbing passion. Self-taught in the photographic craft, he led courses in photography, greatly contributing to the revival of the local photography club.
In the mid-seventies, having enrolled in the Faculty of Political Sciences in Zagreb, he started collaborating with several magazines and newspapers as a freelance photojournalist. In 1979, Pitanja magazine published his experimental photography series Accidental Photos.
His first one-man exhibition in Makarska (1977) was followed by exhibitions in Šibenik (1982) and Zagreb (1987).
He further developed his photographic skill in Radničke novine, a weekly newspaper he joined in 1981 as a photojournalist and photography editor.
In 1991, Antonini moved to Zapad. While on staff there, he also contributed to other major Croatian newspapers and several weeklies. In 1992, already a renowned photojournalist, he joined the Zagreb news bureau of Slobodna Dalmacija and was in 1996 appointed head of the photography department. He continued collaboration with other dailies and magazines, while also being an active member of the Croatian Press Photographers Association. On his many and varied photojournalistic assignments, including an extensive coverage of the war in Croatia, he strived towards maintaining the highest professional standards, creating an expressive and unique photographic style.
He died in a plane crash near Dubrovnik on 3 April 1996, while on assignment from the US Embassy in Croatia to cover a visit of high US officials.
He was posthumously awarded the Order of the Croatian Trefoil.
The annual press photography award of the Croatian Journalists Association was in 1996 named after Nikša Antonini.