On May 21, 1985, in Lake Forest, Illinois, USA, Prince Rostislav Rostislavovich was born. He is a descendant of the Russian Imperial House and the grandson of Prince of Imperial Blood Rostislav Alexandrovich, who was the son of Grand Duke Alexander Mikhailovich and Grand Duchess Ksenia Alexandrovna, a nephew of Emperor Nicholas II, as well as a descendant of Emperors Alexander II and Nicholas I.

Prince Rostislav Rostislavovich belongs to the "Mikhailovich" branch of the Romanovs, descending from Grand Duke Mikhail Nikolaevich, the younger son of Emperor Nicholas I. He is also a descendant of Duchess Sophia of Hanover and is in the line of succession to the British throne. Since December 3, 2017, he has held the position of Vice-Chairman of the Association of Members of the Romanov Family.

As the three sons of the current Head of the Romanov Family, Prince Andrei Andreevich, have no male descendants, Prince Rostislav Rostislavovich is likely to lead the Romanov Family in the future. He is the eldest son and the second child of Prince Rostislav Rostislavovich Senior and his second wife, Kristen Ipsen. He has an older sister, Princess Alexandra Rostislavovna, and a younger brother, Prince Nikita Rostislavovich. From his father's first marriage to Stefania Verdell Cook, he has another older sister, Princess Stefania Rostislavovna.

Prince Rostislav Rostislavovich was baptized by the Cossack priest Father Ioann Sushchenko in London when he was six months old. He was raised in the Russian Orthodox tradition and learned the Russian language at the age of twenty.

He studied visual arts at Falmouth University College in the UK and became an artist. His works have been exhibited in London, Moscow, St. Petersburg, Monte Carlo, Athens, Dubai, and Almaty. He became the first of the Romanovs to return to live permanently in Russia.

In 1998, Rostislav visited Russia with his family to participate in the burial of the presumed remains of Emperor Nicholas II and his family. Six months later, on January 7, 1999, during the Christmas celebration, his father passed away.

Prince Nikolai Romanovich, the former Chairman of the Association of Members of the Romanov Family, appointed Rostislav as the official representative of the Romanov Family in Russia.

On September 12, 2021, in the Alexander Nevsky Cathedral in Paris, the wedding of Prince Rostislav Rostislavovich and Princess Fotinia Philipovna, born Fotonia Maria Christina Georganta, took place. They have a son, Prince Rostislav Rostislavovich Junior.