diff --git a/src/frontend/A64/decoder/a64.inc b/src/frontend/A64/decoder/a64.inc
index d7460c37..8f6411cb 100644
--- a/src/frontend/A64/decoder/a64.inc
+++ b/src/frontend/A64/decoder/a64.inc
@@ -862,7 +862,7 @@ INST(SM3TT2B,                "SM3TT2B",                                   "11001
 //INST(SHA512H2,               "SHA512H2",                                  "11001110011mmmmm100001nnnnnddddd")
 //INST(SHA512SU1,              "SHA512SU1",                                 "11001110011mmmmm100010nnnnnddddd")
 INST(RAX1,                   "RAX1",                                      "11001110011mmmmm100011nnnnnddddd")
-//INST(SM3PARTW1,              "SM3PARTW1",                                 "11001110011mmmmm110000nnnnnddddd")
+INST(SM3PARTW1,              "SM3PARTW1",                                 "11001110011mmmmm110000nnnnnddddd")
 INST(SM3PARTW2,              "SM3PARTW2",                                 "11001110011mmmmm110001nnnnnddddd")
 //INST(SM4EKEY,                "SM4EKEY",                                   "11001110011mmmmm110010nnnnnddddd")
 
diff --git a/src/frontend/A64/translate/impl/simd_sha512.cpp b/src/frontend/A64/translate/impl/simd_sha512.cpp
index 1b87a176..463f3043 100644
--- a/src/frontend/A64/translate/impl/simd_sha512.cpp
+++ b/src/frontend/A64/translate/impl/simd_sha512.cpp
@@ -19,6 +19,44 @@ bool TranslatorVisitor::RAX1(Vec Vm, Vec Vn, Vec Vd) {
     return true;
 }
 
+bool TranslatorVisitor::SM3PARTW1(Vec Vm, Vec Vn, Vec Vd) {
+    const IR::U128 d = ir.GetQ(Vd);
+    const IR::U128 m = ir.GetQ(Vm);
+    const IR::U128 n = ir.GetQ(Vn);
+
+    const IR::U128 eor_d_n = ir.VectorEor(d, n);
+
+    const IR::U128 result_low_three_words = [&] {
+        // Move the top-most 3 words down one element (i.e. [3, 2, 1, 0] -> [0, 3, 2, 1])
+        const IR::U128 shuffled_m = ir.VectorShuffleWords(m, 0b00111001);
+
+        // We treat the uppermost word as junk data and don't touch/use it explicitly for now.
+        // Given we don't do anything with it yet, the fact we EOR into it doesn't matter.
+        return ir.VectorEor(eor_d_n, ir.VectorRotateLeft(32, shuffled_m, 15));
+    }();
+
+    IR::U128 result = result_low_three_words;
+    for (size_t i = 0; i < 4; i++) {
+        if (i == 3) {
+            const IR::U32 top_eor_d_n = ir.VectorGetElement(32, eor_d_n, 3);
+            const IR::U32 low_result_word = ir.VectorGetElement(32, result, 0);
+            const IR::U32 top_result_word = ir.Eor(top_eor_d_n, ir.RotateRight(low_result_word, ir.Imm8(17)));
+
+            // Now the uppermost word is well-defined data.
+            result = ir.VectorSetElement(32, result, 3, top_result_word);
+        }
+
+        const IR::U32 word = ir.VectorGetElement(32, result, i);
+        const IR::U32 modified = ir.Eor(word, ir.Eor(ir.RotateRight(word, ir.Imm8(17)),
+                                                     ir.RotateRight(word, ir.Imm8(9))));
+
+        result = ir.VectorSetElement(32, result, i, modified);
+    }
+
+    ir.SetQ(Vd, result);
+    return true;
+}
+
 bool TranslatorVisitor::SM3PARTW2(Vec Vm, Vec Vn, Vec Vd) {
     const IR::U128 d = ir.GetQ(Vd);
     const IR::U128 m = ir.GetQ(Vm);