diff --git a/ruby/146-LRU-Cache.rb b/ruby/146-LRU-Cache.rb
new file mode 100644
index 000000000..c87160eda
--- /dev/null
+++ b/ruby/146-LRU-Cache.rb
@@ -0,0 +1,74 @@
+class LRUCache
+
+=begin
+ :type capacity: Integer
+=end
+ def initialize(capacity)
+ @capacity = capacity
+ @cache = {}
+ @l = Node.new()
+ @r = Node.new()
+ @l.next = @r
+ @r.prev = @l
+ end
+
+
+=begin
+ :type key: Integer
+ :rtype: Integer
+=end
+ def get(key)
+ return -1 unless @cache.key?(key)
+
+ remove(@cache[key])
+ insert(@cache[key])
+ @cache[key].value
+ end
+
+
+=begin
+ :type key: Integer
+ :type value: Integer
+ :rtype: Void
+=end
+ def put(key, value)
+ remove(@cache[key]) if @cache.key?(key)
+
+ @cache[key] = Node.new(key, value)
+ insert(@cache[key])
+ evict if @capacity < @cache.size
+ end
+
+ private
+ def remove(node)
+ prev = node.prev
+ nxt = node.next
+
+ prev.next = nxt
+ nxt.prev = prev
+ end
+
+ def insert(node)
+ prev = @r.prev
+ prev.next = node
+ @r.prev = node
+
+ node.prev = prev
+ node.next = @r
+ end
+
+ def evict
+ lru = @l.next
+ remove(lru)
+ @cache.delete(lru.key)
+ end
+
+ class Node
+ attr_accessor :value, :prev, :next, :key
+
+ def initialize(key = 0, val = nil)
+ self.value = val
+ self.key = key
+ end
+ end
+end
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