Ly is a unisex given name of Vietnamese origin, derived from the word "ly" which means "reason" or "logic". It gained popularity in the West as a feminine name but is also used for males in Vietnam and among the Vietnamese diaspora. The name Ly is often associated with the historic Ly Dynasty (1010-1225), one of the most prosperous periods in Vietnam's history, named after its founder, Emperor Lý Thái Tổ.
The name Ly experienced notable fluctuations in popularity over the years, peaking with 13 births in 1983 and dropping to as low as 5 births in several later years.