diff --git a/README.md b/README.md
index b971e1d6..ead13d0a 100644
--- a/README.md
+++ b/README.md
@@ -673,6 +673,7 @@ Profile on LeetCode: [fartem](https://leetcode.com/fartem/).
 | 1249. Minimum Remove to Make Valid Parentheses                   | [Link](https://leetcode.com/problems/minimum-remove-to-make-valid-parentheses/)                    | [Link](./lib/medium/1249_minimum_remove_to_make_valid_parentheses.rb)                   | [Link](./test/medium/test_1249_minimum_remove_to_make_valid_parentheses.rb)                   |
 | 1261. Find Elements in a Contaminated Binary Tree                | [Link](https://leetcode.com/problems/find-elements-in-a-contaminated-binary-tree/)                 | [Link](./lib/medium/1261_find_elements_in_a_contaminated_binary_tree.rb)                | [Link](./test/medium/test_1261_find_elements_in_a_contaminated_binary_tree.rb)                |
 | 1288. Remove Covered Intervals                                   | [Link](https://leetcode.com/problems/remove-covered-intervals/)                                    | [Link](./lib/medium/1288_remove_covered_intervals.rb)                                   | [Link](./test/medium/test_1288_remove_covered_intervals.rb)                                   |
+| 1302. Deepest Leaves Sum                                         | [Link](https://leetcode.com/problems/deepest-leaves-sum/)                                          | [Link](./lib/medium/1302_deepest_leaves_sum.rb)                                         | [Link](./test/medium/test_1302_deepest_leaves_sum.rb)                                         |
 | 1400. Construct K Palindrome Strings                             | [Link](https://leetcode.com/problems/construct-k-palindrome-strings/)                              | [Link](./lib/medium/1400_construct_k_palindrome_strings.rb)                             | [Link](./test/medium/test_1400_construct_k_palindrome_strings.rb)                             |
 | 2116. Check if a Parentheses String Can Be Valid                 | [Link](https://leetcode.com/problems/check-if-a-parentheses-string-can-be-valid/)                  | [Link](./lib/medium/2116_check_if_a_parentheses_string_can_be_valid.rb)                 | [Link](./test/medium/test_2116_check_if_a_parentheses_string_can_be_valid.rb)                 |
 | 2425. Bitwise XOR of All Pairings                                | [Link](https://leetcode.com/problems/bitwise-xor-of-all-pairings/)                                 | [Link](./lib/medium/2425_bitwise_xor_of_all_pairings.rb)                                | [Link](./test/medium/test_2425_bitwise_xor_of_all_pairings.rb)                                |
diff --git a/leetcode-ruby.gemspec b/leetcode-ruby.gemspec
index 17a9d6d5..f57c9dff 100644
--- a/leetcode-ruby.gemspec
+++ b/leetcode-ruby.gemspec
@@ -5,7 +5,7 @@ require 'English'
 ::Gem::Specification.new do |s|
   s.required_ruby_version = '>= 3.0'
   s.name = 'leetcode-ruby'
-  s.version = '8.4.0'
+  s.version = '8.4.1'
   s.license = 'MIT'
   s.files = ::Dir['lib/**/*.rb'] + %w[README.md]
   s.executable = 'leetcode-ruby'
diff --git a/lib/medium/1302_deepest_leaves_sum.rb b/lib/medium/1302_deepest_leaves_sum.rb
new file mode 100644
index 00000000..3b7e264f
--- /dev/null
+++ b/lib/medium/1302_deepest_leaves_sum.rb
@@ -0,0 +1,38 @@
+# frozen_string_literal: true
+
+# https://leetcode.com/problems/deepest-leaves-sum/
+# @param {TreeNode} root
+# @return {Integer}
+def deepest_leaves_sum(root)
+  @max_deep = max_deep(root, 0)
+
+  traverse_for_deepest_leaves_sum(root, 0)
+end
+
+private
+
+# @param {TreeNode} node
+# @param {Integer} curr
+# @return {Integer}
+def max_deep(node, curr)
+  return curr unless node
+
+  left = max_deep(node.left, curr + 1)
+  right = max_deep(node.right, curr + 1)
+
+  [left, right].max
+end
+
+# @param {TreeNode} node
+# @param {Integer} curr
+# @return {Integer}
+def traverse_for_deepest_leaves_sum(node, curr)
+  return 0 unless node
+
+  return node.val if curr + 1 == @max_deep
+
+  left = traverse_for_deepest_leaves_sum(node.left, curr + 1)
+  right = traverse_for_deepest_leaves_sum(node.right, curr + 1)
+
+  left + right
+end
diff --git a/test/medium/test_1302_deepest_leaves_sum.rb b/test/medium/test_1302_deepest_leaves_sum.rb
new file mode 100644
index 00000000..17facadd
--- /dev/null
+++ b/test/medium/test_1302_deepest_leaves_sum.rb
@@ -0,0 +1,30 @@
+# frozen_string_literal: true
+
+require_relative '../test_helper'
+require_relative '../../lib/common/binary_tree'
+require_relative '../../lib/medium/1302_deepest_leaves_sum'
+require 'minitest/autorun'
+
+class DeepestLeavesSumTest < ::Minitest::Test
+  def test_case_one
+    assert_equal(
+      15,
+      deepest_leaves_sum(
+        ::TreeNode.build_tree(
+          [1, 2, 3, 4, 5, nil, 6, 7, nil, nil, nil, nil, 8]
+        )
+      )
+    )
+  end
+
+  def test_case_two
+    assert_equal(
+      19,
+      deepest_leaves_sum(
+        ::TreeNode.build_tree(
+          [6, 7, 8, 2, 7, 1, 3, 9, nil, 1, 4, nil, nil, nil, 5]
+        )
+      )
+    )
+  end
+end