The electrochemicalfluorination of a variety of N-protected lactams was carried out and Et3N–5HF was found to be superior to Et3N–3HF as the electrolyte. When 5- and 6-membered N-acetyl or ethoxycarbonyl lactams were used as substrates, the fluorination reaction selectively took place at the α-position of the lactam nitrogen and the corresponding monofluoro products could be obtained in good yields