在计算机科学中，迭代深化搜索（iterative deepening search）或者更确切地说迭代深化深度优先搜索 (iterative deepening depth-first search (IDS or IDDFS)) 是一个状态空间（状态图）搜索策略。在这个搜索策略中，一个具有深度限制的深度优先搜索算法会不断重复地运行，并且同时放宽对于搜索深度的限制，直到找到目标状态。IDDFS 与广度优先算法是等价的，但对内存的使用会少很多；在每一步迭代中，它会按深度优先算法中的顺序，遍历搜索树中的节点，但第一次访问节点的累积顺序实际上是广度优先的。

In computer science, iterative deepening search or more specifically iterative deepening depth-first search (IDS or IDDFS) is a state space/graph search strategy in which a depth-limited version of depth-first search is run repeatedly with increasing depth limits until the goal is found. IDDFS is equivalent to breadth-first search, but uses much less memory; on each iteration, it visits the nodes in the search tree in the same order as depth-first search, but the cumulative order in which nodes are first visited is effectively breadth-first.