To date there have been multiple clinical reports of pediatric patients with Williams Beuren syndrome developing non-Hodgkin lymphoma. However, there is no clear evidence of an association between this microdeletion syndrome and lymphoma risk and as of yet there are no recommendations for cancer surveillance in the follow-up of these patients. In this report we descibe two patients with Williams Beuren syndrome, both of whom were diagnosed with non-Hodgkin lymphoma, one at the age of 2 years and the other at the age of 6 years during clinical follow-up. Although Williams-Beuren syndrome is not a cancer-predisposing genetic syndrome, rare cases of malignancy have been reported in these patients, necessitating consideration of this fact during patient follow-up.