Nissim was born in Constantinople in 1830. He married Elise Fernandez in 1855 and the couple had one son, Moïse. Nissim was the younger brother of Abraham-Behor, to whom he was very close, living alongside him and helping him in all his undertakings.
When he moved to Paris in 1869, Nissim bought a mansion at 63, rue de Monceau, and Abraham-Behor had one built on the adjacent plot. Like his brother, Nissim hosted lavish receptions and assembled collections of paintings and art objects. There was no rivalry between the brothers, who were devoted to each other and united in their desire to be part of Parisian high society, without relinquishing their ties to the East. They became familiar figures at the Paris stock exchange, and the urbane and elegant Nissim was often to be seen at the Opéra, the races and fashionable spa resorts, attracting attention from anti-Semitic writers who were especially virulent at that time.
When Nissim was awarded the Legion of Honor in 1882, he commissioned a portrait from the painter Carolus Duran.
While maintaining close ties to Turkey and taking Paris to their hearts, they also continued to represent Italian interests. Nissim became President of the Italian Welfare Society in Paris, but their most noteworthy position was the presidency of the Italian committee in Paris for the Exposition Universelle of 1889. Nissim, who had taken on the role of president, died in January 1889 and was replaced by his brother Abraham Béhor, who died in his turn at the end of the same year.