The standard American pronunciation of lieu is "loo". Some people who read the word before ever hearing it (it’s a rare word in ordinary speech, more common in

The standard American pronunciation of lieu is "loo". Some people who read the word before ever hearing it (it’s a rare word in ordinary speech, more common in writing), or maybe took a high school French class and want to sound fancy, say something like "lyoo" instead, but this is non-standard and uncommon. (Neither of the two is a correct pronunciation in French.)