diff --git a/src/insn.c b/src/insn.c
index 1a1a223..1758719 100644
--- a/src/insn.c
+++ b/src/insn.c
@@ -89,6 +89,15 @@ void insn_sw(cpu_t *cpu, uint32_t insn) {
     cpu_write32(cpu, cpu->regs[rt], imm + cpu->regs[rs]);
 }
 
+void insn_sll(cpu_t *cpu, uint32_t insn) {
+    const uint8_t rd = RD(insn);
+    const uint8_t rt = RT(insn);
+    const uint8_t imm5 = IMM5(insn);
+
+    debug("SLL %s, %s, %u", REG_NAMES[rd], REG_NAMES[rt], imm5);
+    cpu->regs[rd] = cpu->regs[rt] << imm5;
+}
+
 static cpu_insn_handler primary_insn_handler[TABLE_SIZE] = {
     [LW] = insn_lw,
     [ADDIU] = insn_addiu,
@@ -96,6 +105,7 @@ static cpu_insn_handler primary_insn_handler[TABLE_SIZE] = {
 };
 
 static cpu_insn_handler secondary_insn_handler[TABLE_SIZE] = {
+    [SLL] = insn_sll,
     [ADDU] = insn_addu,
     [SRL] = insn_srl,
 };