Samoa scored 31 seconds into the match as Ken Pisi handed the series giants a five point lead with the first try of the match as captain Uale Mai extended it to seven points with a well executed conversion.
Oscar Ouma then levelled it out for Kenya two minutes into as Nato Simiyu converted to give the upstarts fresh hopes.
Matters took a different turn for Kenya when Collins Injera was sent to the sin bin, and it was not long before Samoa pressed their numerical advantage with a Paul Perez try.
Samoa took control of the game in the second half with the only try coming three minutes in courtesy of Alatasi Tupou, the match ending 19-7 in favour of the USA Sevens champions.
Kenya will face another formidable side, England before completing their Group A pool fixtures with a date against Argentina in games they need to win to make the Main Cup quarters.
Crowd favourites England beat Argentina at the end of a breathless first day’s play where the top six in the HSBC Sevens World Series standings were all made to work hard for opening pool wins at the Cathay Pacific/ HSBC Hong Kong Sevens.
England who are fourth in the World Series standings and got off to a winning start in front of the ex-pat crowd, beating Argentina 19-10 thanks to tries from Dan Norton, Rob Vickerman and Mat Turner.