The aim of this study was to evaluate the ability of axillary ultrasound (US) and US-guided fine-needle aspiration biopsy (FNAB) to detect axillary LN metastases. Between January 2001 and September 2003, axillary US was performed in 165 patients with cytologically or histologically proven breast cancer and clinically non-palpable axillary LNs. In patients with US suspicious LNs, US-guided FNAB was performed and patients with cytologically proven malignant LNs proceeded directly to the ALND. In 49/90 patients with US suspicious LNs, US-guided FNAB was performed. It was positive in 33/49 patients. Definitive histology report revealed LN metastases in 65/165 patients. The sensitivity, specificity, positive and negative predictive value of the US-FNAB, were 84, 91, 97 and 62%. Axillary US in a combination with US-FNAB is a valuable method in preoperative staging of patients with breast cancer. Almost 50% of patients with LN metastases can be spared the second operation. However, it is very much operator-dependent and equipment-dependent.