Longidorus reisi sp. n. is described and figured. It was found at Quinta do Anjo, Palmela, Portugal, in the rhizosphere of peach. The new species is characterized by the female having a long (9.2 mm) rather thin body, an expanded lip region, asymmetrically bilobed amphidial pouches and a conical tail two to three anal body widths long. Male were not found. L reisi sp. n. is similar to L alvegus Roca, Pereira & Lamberti, 1989, L arenosus Kankina & Ivanova, 1986, L euonymus Mali & Hooper, 1973, L. pini Andres & Arias, 1987 and L unedoi Arias, Andres & Navas, 1986. The most significant differences from all these species are in the body, odontostyle, and tail all being longest in L reisi sp. n.