Our objective is to present a case of proximal tibial osteomyelitis due to Salmonella, which is infrequent in clinical practice, as well as to analyze the procedures carried out for its treatment, and the differential diagnosis of the lesion. Clinical case: A 13-year-old male referred from another Hospital to our Hospital Children's Oncology due to a suspicion of a bone tumor in the tibia. The patient reported two-week history of knee pain associated with fever. In the radiographs taken at his center, a lytic lesion was observed in the proximal metaphysis of the tibia, which led to the performance of a Magnetic Resonance Imaging (MRI). After reviewing the MRI images in our center, the neoplastic nature of the lesion was ruled out and the suspected diagnosis was an Osteomyelitis, after which the patient underwent surgery, being performed a corticotomy and emptying of the abscess and initiating intravenous antibiotic treatment. The patient had an unremarkable postoperative course and in the culture of the extracted material Salmonella group B was obtained. The patient was controlled with oral antibiotic, and was definitively discharged two years after the intervention. However, 3 years after that, he came to Hospital with similar symptoms. After performing some imaging tests, two multiloculated lytic lesions were observed in the proximal tibia with a perilesional inflammatory reaction, suggestive of recurrence of Osteomyelitis, for which he underwent surgery again, performing a bone window and curettage, and filling the cavity with tricalcium sulfate and antibiotic. The cultures taken were again positive for Salmonella B. After the patient's clinical and analytical progress was correct, he was treated with oral antibiotics, and was definitively discharged two years after the intervention. Conclusion: Salmonella osteomyelitis in immunocompetent patients is a rare pathology that can simulate a neoplastic lesion if it is found in an atypical location such as metaphysis. The diagnosis must be clinical, radiological and analytical, although the definitive diagnosis will be achieved by cultures results. The definitive treatment is curettage and filling the lesion, associated with antibiotic therapy, and it is necessary to take into account that the lesion may recur.