diff --git a/src/Functions/LowerUpperImpl.h b/src/Functions/LowerUpperImpl.h
index a7c38a7f904..ca3b7173032 100644
--- a/src/Functions/LowerUpperImpl.h
+++ b/src/Functions/LowerUpperImpl.h
@@ -29,31 +29,61 @@ private:
     {
         const auto flip_case_mask = 'A' ^ 'a';
 
+#if defined(__AVX512F__) && defined(__AVX512BW__) /// check if avx512 instructions are compiled
+        if (isArchSupported(TargetArch::AVX512BW))  
+        {
+            /// check if cpu support avx512 dynamically, haveAVX512BW contains check of haveAVX512F
+            const auto byte_avx512 = sizeof(__m512i);
+            const auto src_end_avx = src_end - (src_end - src) % byte_avx512;
+            if (src < src_end_avx) {
+                const auto v_not_case_lower_bound = _mm512_set1_epi8(not_case_lower_bound - 1);
+                const auto v_not_case_upper_bound = _mm512_set1_epi8(not_case_upper_bound + 1);
+                const auto v_flip_case_mask = _mm512_set1_epi8(flip_case_mask);
+
+                for (; src < src_end_avx; src += byte_avx512, dst += byte_avx512) {
+                    const auto chars = _mm512_loadu_si512(reinterpret_cast<const __m512i *>(src));
+
+                    const auto is_not_case
+                            = _mm512_and_si512(_mm512_movm_epi8(_mm512_cmpgt_epi8_mask(chars, v_not_case_lower_bound)), 
+                            _mm512_movm_epi8(_mm512_cmplt_epi8_mask(chars, v_not_case_upper_bound)));
+
+                    const auto xor_mask = _mm512_and_si512(v_flip_case_mask, is_not_case);
+
+                    const auto cased_chars = _mm512_xor_si512(chars, xor_mask);
+
+                    _mm512_storeu_si512(reinterpret_cast<__m512i *>(dst), cased_chars);
+                }
+            }
+        }
+#endif
+
 #ifdef __SSE2__
         const auto bytes_sse = sizeof(__m128i);
         const auto * src_end_sse = src_end - (src_end - src) % bytes_sse;
-
-        const auto v_not_case_lower_bound = _mm_set1_epi8(not_case_lower_bound - 1);
-        const auto v_not_case_upper_bound = _mm_set1_epi8(not_case_upper_bound + 1);
-        const auto v_flip_case_mask = _mm_set1_epi8(flip_case_mask);
-
-        for (; src < src_end_sse; src += bytes_sse, dst += bytes_sse)
+        if (src < src_end_sse)
         {
-            /// load 16 sequential 8-bit characters
-            const auto chars = _mm_loadu_si128(reinterpret_cast<const __m128i *>(src));
+            const auto v_not_case_lower_bound = _mm_set1_epi8(not_case_lower_bound - 1);
+            const auto v_not_case_upper_bound = _mm_set1_epi8(not_case_upper_bound + 1);
+            const auto v_flip_case_mask = _mm_set1_epi8(flip_case_mask);
 
-            /// find which 8-bit sequences belong to range [case_lower_bound, case_upper_bound]
-            const auto is_not_case
-                = _mm_and_si128(_mm_cmpgt_epi8(chars, v_not_case_lower_bound), _mm_cmplt_epi8(chars, v_not_case_upper_bound));
+            for (; src < src_end_sse; src += bytes_sse, dst += bytes_sse)
+            {
+                /// load 16 sequential 8-bit characters
+                const auto chars = _mm_loadu_si128(reinterpret_cast<const __m128i *>(src));
 
-            /// keep `flip_case_mask` only where necessary, zero out elsewhere
-            const auto xor_mask = _mm_and_si128(v_flip_case_mask, is_not_case);
+                /// find which 8-bit sequences belong to range [case_lower_bound, case_upper_bound]
+                const auto is_not_case
+                    = _mm_and_si128(_mm_cmpgt_epi8(chars, v_not_case_lower_bound), _mm_cmplt_epi8(chars, v_not_case_upper_bound));
 
-            /// flip case by applying calculated mask
-            const auto cased_chars = _mm_xor_si128(chars, xor_mask);
+                /// keep `flip_case_mask` only where necessary, zero out elsewhere
+                const auto xor_mask = _mm_and_si128(v_flip_case_mask, is_not_case);
 
-            /// store result back to destination
-            _mm_storeu_si128(reinterpret_cast<__m128i *>(dst), cased_chars);
+                /// flip case by applying calculated mask
+                const auto cased_chars = _mm_xor_si128(chars, xor_mask);
+
+                /// store result back to destination
+                _mm_storeu_si128(reinterpret_cast<__m128i *>(dst), cased_chars);
+            }
         }
 #endif