diff --git a/tree/BST.py b/tree/BST.py
new file mode 100644
index 0000000..e06f861
--- /dev/null
+++ b/tree/BST.py
@@ -0,0 +1,175 @@
+from xmlrpc.client import Boolean
+
+
+class BinaryTreeNode:
+	def __init__(self, data:any, left=None,  right=None) -> None:
+		self.data:any = data
+		self.left:BinaryTreeNode = left
+		self.right:BinaryTreeNode = right
+
+class BST:
+	def __init__(self, root=None) -> None:
+		if root:
+			self.root = root
+			self.len = 1
+		else:
+			self.root = BinaryTreeNode(None)
+			self.len = 0
+
+	def insert(self, node, child) -> None:
+		if node.data == child.data:
+			return
+
+		if node.data < child.data:
+			if node.right is None:
+				node.right = child
+			else:
+				self.insert(node.right, child)
+		
+		elif node.data > child.data:
+			if node.left is None:
+				node.left = child
+			else:
+				self.insert(node.left, child)
+
+		self.len += 1
+		
+
+
+	def find_node(self, node, data) -> None:
+		# root node를 안넣으면 어떻게 되지?
+		if node is None:
+			return None
+		
+		if node.data == data:
+			return node
+		if node.data > data:
+			return self.find_node(node.left, data)
+		if node.data < data:
+			return self.find_node(node.right, data)
+	
+
+	def find_min_node(self, node):
+		if node is None:
+			return None
+
+		if node.left is None:
+			return node
+		else:
+			return self.find_min_node(node.left)
+
+
+	def remove(self, node, parent, target_data):
+		removed = None
+		
+		if node is None:
+			return None
+
+		if (node.data > target_data):
+			removed = self.remove(node.left, node, target_data)
+		elif (node.data < target_data):
+			removed = self.remove(node.right, node, target_data)
+		else:
+			removed = node
+		
+			if not node.left  and not node.right :
+				if parent.left == node:
+					parent.left = None
+				else:
+					parent.right = None
+
+			else:
+				if node.left and node.right:
+					min_node = self.find_min_node(node.right)
+					removed = self.remove(node, None, min_node.data)
+					node.data = min_node.data
+				else:
+					temp = None
+					if node.left:
+						temp = node.left
+					else:
+						temp = node.right
+					
+					if parent.left == node:
+						parent.left = temp
+					else:
+						parent.right = temp
+		
+		self.len -= 1
+
+		return removed
+
+
+
+	def print(self, node):
+		if node is None:
+			return
+
+		self.print(node.left)
+
+		print(f"[ {node.data} ]")
+
+		self.print(node.right)
+
+	def to_list(self, node, result):
+		if node is None:
+			return
+		
+		self.to_list(node.left, result)
+		result.append(node.data)
+		self.to_list(node.right, result)
+
+		return result
+		
+def pretty_print(to_print:str) -> None:
+	print()
+	print(f" * * * {to_print} * * * ")
+	print()
+
+def main():
+	root = BinaryTreeNode(50)
+	bs_tree = BST(root=root)
+	data_size = 5
+	for i in range(1, data_size):
+		bs_tree.insert(root, BinaryTreeNode(50 - 10 * i))
+		bs_tree.insert(root, BinaryTreeNode(50 - 10 * i + 1))
+		bs_tree.insert(root, BinaryTreeNode(50 - 10 * i - 1))
+		bs_tree.insert(root, BinaryTreeNode(50 + 10 * i))
+		bs_tree.insert(root, BinaryTreeNode(50 + 10 * i + 1))
+		bs_tree.insert(root, BinaryTreeNode(50 + 10 * i - 1))
+
+	pretty_print("initial tree")
+
+	result = bs_tree.to_list(root, [])
+	print(result)
+	print(40 in result)
+
+	removed = bs_tree.remove(root, None, 40)
+	print(f"removed is {removed.data}")
+	pretty_print("after remove tree")
+
+	result = bs_tree.to_list(root, [])
+	print(result)
+	print(40 not in result)
+
+	#to_update = bs_tree.find_node(root, 21)
+	#bs_tree.print(to_update)
+	#print(to_update.data)
+	#to_update.data = 99
+	#result = bs_tree.to_list(root, [])
+	#print(result)
+
+	pretty_print("print partial")
+	to_print = bs_tree.find_node(root, 10)
+	bs_tree.print(to_print)
+
+
+
+
+
+if __name__ == "__main__":
+	main()
+
+
+
+