Joint disorders in children are a frequent cause of parents’ concern and a reason of visiting family doctors and rheumatologists. In search for the correct diagnosis, a wide differential diagnosis should be conducted, including bacterial, parasitic, but also rheumatoid or proliferative process. However, the majority of complaints reported by children are reactive in nature. Diagnosis is based on the clinical symptoms and serology tests results. Ascaris lumbricoides or Toxocara canis infection may manifest itself not only with gastrointestinal, but also musculoskeletal symptoms, depending on the period of the disease. The aim of the paper was to assess the frequency of complaints associated with the locomotor system in children with the presence of serum antibodies against Ascaris lumbricoides and/or Toxocara canis and to analyse their relationship with selected laboratory tests (eosinophilia) and the final diagnosis. Material and methods: Medical records of 86 children hospitalised in 2013–2015 at the Department of Paediatric Cardiology and Rheumatology, Medical University of Łódź, were analysed. Children with musculoskeletal symptoms and positive serum antibody titres against Ascaris lumbricoides and/or Toxocara canis were included in the study. Results: Among the infected patients, the most frequently reported complaint from the locomotor system was knee (51%) and wrist (19%) pain. Ascaris lumbricoides infection was the dominant human parasitosis (66%), while in 15 patients (17%) Toxocara canis co-infestation was detected. Rheumatoid process was the most common suspicion (36%), but the final diagnosis of juvenile idiopathic arthritis was determined in only 12 patients (14%). Conclusions: Parasitic infections often coexist with articular symptoms reported by children and should always be excluded in the differential diagnosis. In some cases, a parasitic infection may be one of the factors that initiate the rheumatoid process.