Rennie's stock rose in Scotland's disappointing RBS 6 Nations campaign, with the openside flanker among the nominees for player of the championship. Rennie, 26 tomorrow, now has 16 caps.
Both Rennie and centre De Luca, 28 and with 33 caps, are tied to the capital club until 2014.
Edinburgh head coach Michael Bradley said: "It's fantastic news for Edinburgh Rugby that players of the calibre of Ross and Nick have committed these crucial years of their rugby careers to the club."
Nineteen players have been retained by Bradley for next season, with the confirmation of deals for Rennie and De Luca a major boost ahead of the Heineken Cup quarter-final with Toulouse on Easter Saturday.
Rennie, whose international career stalled after his debut in 2008 due to a serious knee injury, said: "Having grown up in Edinburgh it means a lot to me to represent this club so I'm delighted to have extended my contract and to have secured the chance to play for the club I grew up supporting.
"Personally I'm in a good place just now. I'm happy with the way I'm playing for both the club and Scotland.
"I've made these developments as a player at this club and I'm confident that this is the right place for me to continue to improve.
"There's a lot of optimism about where we're going and I'm looking forward to being a part of that future."
De Luca added: "I'm really enjoying my rugby in Edinburgh. Our progress in the Heineken Cup has made this season a real landmark for even the most experienced players.
"Despite these highlights it's clear to all the players that we have opportunities to improve as individuals and as a team, combining a committed group of players who are signing on to something special with exciting new arrivals in the seasons ahead."
Gilbert has released a new line of rugby cleats. The Gilbert Virtuo 8S is part of the exciting new product. Check it out.
The entire All Blacks apparel line has been updated for 2013/14. Check out the New Zealand All Blacks polo.
The Nike Tiempo is a solid rugby cleat and one of few styles still made from full-grain natural leather.
The Gilbert Blitz 8S rugby cleat is a great cleat at a great price of $69.99. Get a new pair of cleats today.
A cool looking all black rugby cleat with the high performance adidas is known for. Get in the Gear!
Wear the crest of the British and Irish Lions on your t-shirt. A great look for the summer.
The All Blacks Performance t-shirt is black with hints of blue from the training jersey. Very Cool.
The New Zealand All Blacks training jersey for 2013/14. Get in the Gear!
The USA Rugby Pro Alternate rugby jersey is perfect for any fan of the Eagles. Get yours to wear during the summer Test matches.
The NEW All Blacks 2013/14 jersey has arrived at World Rugby Shop. Dare to wear the colors of the All Blacks.