What was the last production year for the Honda nighthawk 750?

1993 was the last production year of the Nighthawk. Source: http://hondanighthawks.net/750.htm

No, it was 2003 for the Nighthawk 750.

The little Nighthawk 250 is still being made. Both were introduced in 1991. The 750 was Motorcycle of the Year that year.