Cystic higromas are the most common soft tissue tumor that are seen in the upper extremity. However the ganglion cysts originated from the shoulder articulation and arm muscles are rarely seen. An eight month female baby was taken to our clinic having enlarging tumor on the right arm. After physical examination and radiological assesment, the patient operated with preoperative diagnosis of atypical localized congenital cystic higroma and diagnosed with histopatological cystic higroma has been discussed with the surgical results. After surgery no complication has been observed for four years.