No, they are not ordered. As long as you don't add or remove any elements from the dictionary, they will remain in the same order, but as soon as you add or remove an element, the new order will be completely different.
If you need the keys/values to be ordered, use an NSArray (or some other ordered data structure) instead.
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…