Broad missed the limited-overs series defeat to India due to a heel injury and Giles claims that the bowler's experience will be vital for the forthcoming matches against New Zealand.
The former Warwickshire coach said: "Stuart has got a major part to play in all three forms of the game for us.
"We've got a lot of strength in depth at the moment. We showed that by taking a relatively inexperienced bowling attack to India for the one-dayers, and leaving some really good players behind.
"That's a key for us. We need to look after our good players really well, keep them hungry and on top of their game."
England face a New Zealand XI in a Twenty20 warm-up match on Monday.