Quinoa plant is a new crop in Egypt and have recently gained global and local attention, especially for its ability to grow under various biotic and abiotic stresses. Currently, there are no studies related to the reaction of the nematodes on quinoa in Egypt and only few studies worldwide. The present study aimed to determine the distribution and prevalence of plant parasitic nematodes associated with quinoa and to evaluate their reaction on plants health and yield of different quinoa genotypes grown in Egypt. An investigation was carried out in Ismailia Governorate during two growing seasons 2020/2021 and 2021/2022. The results revealed the presence of four plant parasitic nematode genera which were Meloidogyne, Pratylenchus, Xiphinema and Longidorus. It has been observed that Xiphinema spp. was the most predominant species in the soil, followed by Meloidogyne spp. and Pratylenchus spp., respectively. The reproduction factors of nematodes (RF) highlighted differential responses among the tested quinoa genotypes ranging from immune to sensitive. The results showed that yield injury (YI) as a result of nematode infection ranged from 12.61 to 28.05%. According to both yield injury and nematode tolerance index (NTI), the tested quinoa genotypes can be divided into three groups under nematode infestation conditions compared to normal conditions, represented by a high resistance group which includes the genotypes G1, G50 and G2, a medium resistance group including the genotypes G29, G44, G78 and G105, and a low resistance group which include the genotypes G23, G49 and G111.