This article explores the phenomenon of code-switching, specifically focusing on bilingual Arabic-Italian determiner phrases which consist of a determiner, such as an article or a demonstrative, followed by a noun phrase as a complement. The data examined were selected from a corpus of Arabic-Italian spontaneous speech with the aim of (1) comparing and describing the characteristics and differences of the determiner systems of the two languages; (2) illustrating the features of code-switching in determiner phrases and the various types found in the collected data; and (3) studying the mutual influence of the two languages in contact contexts. The data analysis revealed two types of code-switching: switching at the beginning of a determiner phrase, where both the determiner and its complement are in the same language, and switching within a determiner phrase, where the determiner and the head noun are from different languages. This latter category also includes determiner phrases with double determiners, which will be analyzed in detail in this article to discuss the features of this linguistic structure in Arabic-Italian bilingual phrases.