Nagai Naohiro (永井 直敬, 1664 – July 18, 1711) was a Japanese daimyō of the Edo period, who ruled the Akō Domain following its confiscation from Asano Naganori.

[1] Naohiro was the eldest son of Nagai Naotsune, and assumed family headship after his father's death.

Upon the confiscation of the Nasu clan's territory in Shimotsuke Province, Naohiro was transferred there from his previous holdings in Kawachi, and thus became the lord of the Karasuyama Domain.

However, because of the time-consuming nature of his work as jisha-bugyō, the domain's affairs were run by his retainers.

Naohiro's grave is at Kōunji Temple, in Nakano City, Tokyo.