"We are delighted to have a fixture of this calibre at the Sportsground, it continues a tradition of national teams visiting the west.
"Portugal played here the year before last and South Africa played here in 2007, the year they went onto win the World Cup, so we are well used to hosting teams from other nations.
"Season tickets will be valid for this match and we are hoping that the midweek fixture will enable plenty of people who cannot make weekend games to attend."
Connacht Rugby has a long association with Samoa, indeed current squad members, Niva Ta'auso and Ray Ofisa, were both born in Samoa.
Gavin Williams and Ofisa Treviranus, Ray's younger brother, have both been capped by the Samoan national side having played with Connacht.
Samoa will play Ireland, England and Scotland before returning to play a one-off Test match against Japan as part of their tour to the Northern Hemisphere.