Tetranychus urticae is the most important pest on different crops worldwide. Search for endemic phytoseiid mites co-occurring with the above pest, which might be good candidates as biocontrol agents, represents the policy followed by most scientists in recent years. The aim of the present work was to assess the various biological and demographic parameters of Neoseiulus longilaterus, associated with T. urticae on weeds, in laboratory conditions using the latter tetranychid and pollen of Oxalis pes-caprae as food. The results showed a better performance of the predator on the prey as regards the postembryonic development (7.63 and 8.18 days for prey and pollen respectively) and the demographic parameters (r_m 0.158 and 0.102, Ro 26.89 and 18.76, DT 4.39 and 6.78 for T. urticae and Oxalis respectively). Our data shows that N. longilaterus have similar traits with some phytoseiid species belonging to type II selective predators, but also with some others included within type III generalist predators. As a matter of fact, it can be considered an interesting biocontrol agent towards T. urticae, able also to develop on alternative foods as the pollen of Oxalis.