The two pools were confirmed on Monday after New Zealand accepted an invitation to play in Brazil.
The Dutch are ranked number two in the world with Germany third, while Ireland will also take on Argentina, India and Canada in Pool B.
"We're know how tough the tournament is and that we're in a tough group," said Irish coach Craig Fulton.
Argentina (sixth) and India (seventh) are above Ireland (12th) in the rankings with Canada 14th.
Pool A comprises Australia, Great Britain, Belgium, New Zealand, Spain and host Brazil.
"We will be focusing on improving as individuals, and as a squad and team come Rio," added Fulton.
"Our first training camp is in early January and we're looking forward to starting 2016 with a tough but enjoyable tour."
The match schedule for all pool games and the play-off stages will be announced in February.

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Bury's Quigg will put his WBA belt on the line against Belfast's Frampton, the IBF champion, at Manchester Arena.
"There's something different about this fight as the rivalry has been so long. It's exciting me in a way that no other fight has before," said Frampton, 29.
"I'm not expecting an easy night but if I'm clever I'll be alright."
"Making this fight happen has been talked about for so long. It has been a long time coming," added the Northern Ireland boxer.
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Both men are unbeaten in their professional careers, making it the most eagerly-anticipated domestic match-up for some time.
"It's a big occasion but I've been involved in big fights and big atmospheres before.
"I'm relaxed, ready and raring to go. I feel like a kid at Christmas, I'm super-excited and can't wait to get going.
"I've been in camp for a long time as I wanted to make sure I was fully prepared. I'm in the shape of my life and my weight is perfect, it's the easiest I've ever made it."
Frampton will rely on the backing of a large travelling support to help cheer him to victory on English soil.
"I'll have 70% of the support in the arena on the night and I know my fans will make a lot of noise.
"The home fighter will have fewer fans than the away fighter and I'm not sure how Scott's going to deal with that.
"I know I have the punching power to take him out, whether it be in the first round or the 12th. I also possess the boxing brain to comprehensively beat him on points.
"My power has been massively underestimated - they are making Quigg out to be this ferocious puncher but I can punch just as hard, if not harder."
Ireland's pool opponents at the Rio Olympics will include defending champions Germany and the Netherlands.
[NEXT_CONCEPT]
Carl Frampton says his long-standing rivalry with Scott Quigg will add spice to Saturday's world super-bantamweight unification fight in Manchester.