Nowadays, recreational fisheries (REC) have a great impact on marine ecosystems and create conflicts with other human coastal activities such as commercial small-scale fisheries (SSF). In the proposed “Taza” marine protected area (MPA) (Algeria, SW Mediterranean), recreational boat fishing is poorly regulated and its catches remain unmonitored. In addition, a significant number of REC fishers sell their catch illegally, an activity we could refer to as IUU (Illegal, Unreported, and Unregulated) fishing. This study is a good opportunity to evaluate the potential conflicts between recreational IUU and commercial fisheries and can be extremely valuable in terms of MPA planning and fisheries monitoring by providing baseline data for setting up sound fisheries management and conservation plans. Two fishing harbors are located near the proposed “Taza” MPA: Boudis and Ziama. Illegal REC boats from Ziama harbor were studied via a direct observation method of landings developed by the Ifremer (French Research Institute for Exploitation of the Sea). A comparison between illegal REC and SSF boats was highlighted in terms of catches and fishing effort. A total of 54 taxa belonging to 24 families were observed in the catches of the 32 recreational active boats in this harbor between May 2013 and April 2014. The proportion of the harvest attributed to illegal REC represented about 50% of the SSF harvest. Illegal REC in the proposed “Taza” MPA is an important socioeconomic activity which is intensively practiced throughout the year. From November to April, the mean catch was almost the same for both fishing categories. Strong competition between recreational and professional fishers for the natural resources was highlighted as 81% of the 54 caught taxa were present in the catches of both fishing categories (i.e. 44 taxa). Moreover, 4 species of high commercial value were caught exclusively by recreational fishers. Finally, the managers of the proposed “Taza” MPA must address and regulate all fishing activities and use the best available information in order to provide important benefits to marine ecosystems, fishers, and the local population.