One of the most interesting aspects of the artistic career of Giuseppe De Nittis (1846-1884), leader of the so-called "Italian Impressionism" in Paris, is the close connection between the dynamics of his personal life and those of his collecting. Until his death, the artistic spirit of the Italian painter, on the one hand, was conditioned by socio-economic demands resulting from the bovarysm of his wife Léontine, while, on the other hand, he showed a resolute and natural propensity toward the Impressionist creed, which he welcomed however in a ‘moderate’ way. In this context, De Nittis related to some members of the French avant-garde becoming sometimes a collector of their works and, at his turn, being 'collected' by them. That of the Italian painter was a modest collection, but which allows one to analyse his dichotomous and conflicting approach to the French movement: in some respects, collecting the Impressionism, De Nittis collected the artistic and ethical principles in which he strongly believed since his youth in Naples, but that he could no longer embrace because of the dizzying work to support the costs of social ambitions of his wife. This artistic duality of the Italian painter essentially ended up splitting his activity between obligation and delight, making him a 'transformer' of the French scene of the second half of the Nineteenth Century.