The Ninja Gaiden series first game was Ninja Gaiden released on 28th February 1989.
1989
Ninja Gaiden
28th February 1989
1990
Ninja Gaiden II: The Dark Sword of Chaos
30th April 1990
1991
Ninja Gaiden III: The Ancient Ship of Doom
21st June 1991
1992
Ninja Gaiden Shadow
9th January 1992
1995
Ninja Gaiden Trilogy
10th August 1995
1999
1st November 1999
2004
2nd March 2004
2005
Ninja Gaiden Black
20th September 2005
2007
Ninja Gaiden Sigma
14th June 2007
15th October 2007
2008
18th February 2008
Ninja Gaiden: Dragon Sword
20th March 2008
Ninja Gaiden II
3rd June 2008
2009
28th July 2009
Ninja Gaiden Sigma 2
29th September 2009
2012
22nd February 2012
Ninja Gaiden 3
20th March 2012
Ninja Gaiden 3: Razor's Edge
18th November 2012
2013
Ninja Gaiden Sigma 2 Plus
26th February 2013
2nd April 2013
22nd August 2013
28th November 2013
2014
Yaiba: Ninja Gaiden Z
18th March 2014
2015
26th November 2015