The Belgian's decision to concentrate on preparing for the defence of her French Open title in May removes the possibility of an eagerly-anticipated clash with former world number one Serena Williams.
Williams will play the NASDAQ-100 in Miami -- her first tournament since Wimbledon July 2003.
"You know, you have to make choice in your life, in your career," Henin-Hardenne told reporters at the Pacific Life Open in Indian Wells this week.
"For me it's a choice."
Instead the Belgian will play a claycourt tournament in Amelia Island, a week after the NASDAQ 100-Open.
"For me, I like to play on clay court. I want to be ready for sure for the French Open. And I need a couple of tournaments."
"It's my favourite surface. That's just question of choices. Two big tournaments in a row, I think it's a little bit too much."
Henin-Hardenne plays Svetlana Kuznetsova in the quarter-finals of the hardcourt Pacific Life Open later on Thursday.