diff --git a/gnovm/pkg/gnolang/gno_test.go b/gnovm/pkg/gnolang/gno_test.go
index 37b590b1c4c..751534e1e16 100644
--- a/gnovm/pkg/gnolang/gno_test.go
+++ b/gnovm/pkg/gnolang/gno_test.go
@@ -39,6 +39,75 @@ func main() {
 	m.RunMain()
 }
 
+func TestDoOpEvalBaseConversion(t *testing.T) {
+	m := NewMachine("test", nil)
+
+	type testCase struct {
+		input     string
+		expect    string
+		expectErr bool
+	}
+
+	testCases := []testCase{
+		// binary
+		{input: "0b101010", expect: "42", expectErr: false},
+		{input: "0B101010", expect: "42", expectErr: false},
+		{input: "0b111111111111111111111111111111111111111111111111111111111111111", expect: "9223372036854775807", expectErr: false},
+		{input: "0b0", expect: "0", expectErr: false},
+		{input: "0b000000101010", expect: "42", expectErr: false},
+		{input: " 0b101010", expectErr: true},
+		{input: "0b", expectErr: true},
+		{input: "0bXXXX", expectErr: true},
+		{input: "42b0", expectErr: true},
+		// octal
+		{input: "0o42", expect: "34", expectErr: false},
+		{input: "0o0", expect: "0", expectErr: false},
+		{input: "042", expect: "34", expectErr: false},
+		{input: "0777", expect: "511", expectErr: false},
+		{input: "0O0000042", expect: "34", expectErr: false},
+		{input: "0777777777777777777777", expect: "9223372036854775807", expectErr: false},
+		{input: "0o777777777777777777777", expect: "9223372036854775807", expectErr: false},
+		{input: "048", expectErr: true},
+		{input: "0o", expectErr: true},
+		{input: "0oXXXX", expectErr: true},
+		{input: "0OXXXX", expectErr: true},
+		{input: "0o42x42", expectErr: true},
+		{input: "0O42x42", expectErr: true},
+		{input: "0420x42", expectErr: true},
+		{input: "0o420o42", expectErr: true},
+		// hex
+		{input: "0x2a", expect: "42", expectErr: false},
+		{input: "0X2A", expect: "42", expectErr: false},
+		{input: "0x7FFFFFFFFFFFFFFF", expect: "9223372036854775807", expectErr: false},
+		{input: "0x2a ", expectErr: true},
+		{input: "0x", expectErr: true},
+		{input: "0xXXXX", expectErr: true},
+		{input: "0xGHIJ", expectErr: true},
+		{input: "0x42o42", expectErr: true},
+		{input: "0x2ax42", expectErr: true},
+		// decimal
+		{input: "42", expect: "42", expectErr: false},
+		{input: "0", expect: "0", expectErr: false},
+		{input: "0000000000", expect: "0", expectErr: false},
+		{input: "9223372036854775807", expect: "9223372036854775807", expectErr: false},
+	}
+
+	for _, tc := range testCases {
+		m.PushExpr(&BasicLitExpr{
+			Kind:  INT,
+			Value: tc.input,
+		})
+
+		if tc.expectErr {
+			assert.Panics(t, func() { m.doOpEval() })
+		} else {
+			m.doOpEval()
+			v := m.PopValue()
+			assert.Equal(t, v.V.String(), tc.expect)
+		}
+	}
+}
+
 func TestEval(t *testing.T) {
 	t.Parallel()
 
diff --git a/gnovm/pkg/gnolang/op_eval.go b/gnovm/pkg/gnolang/op_eval.go
index 83dd3737b6b..3eadbeabfc9 100644
--- a/gnovm/pkg/gnolang/op_eval.go
+++ b/gnovm/pkg/gnolang/op_eval.go
@@ -47,8 +47,8 @@ func (m *Machine) doOpEval() {
 			bi := big.NewInt(0)
 			// TODO optimize.
 			// TODO deal with base.
-			if len(x.Value) > 2 && x.Value[0] == '0' {
-				var ok bool = false
+			var ok bool
+			if len(x.Value) >= 2 && x.Value[0] == '0' {
 				switch x.Value[1] {
 				case 'b', 'B':
 					_, ok = bi.SetString(x.Value[2:], 2)
@@ -56,6 +56,8 @@ func (m *Machine) doOpEval() {
 					_, ok = bi.SetString(x.Value[2:], 8)
 				case 'x', 'X':
 					_, ok = bi.SetString(x.Value[2:], 16)
+				case '0', '1', '2', '3', '4', '5', '6', '7':
+					_, ok = bi.SetString(x.Value, 8)
 				default:
 					ok = false
 				}
diff --git a/gnovm/tests/files/base_conv0.gno b/gnovm/tests/files/base_conv0.gno
new file mode 100644
index 00000000000..381d10cdc98
--- /dev/null
+++ b/gnovm/tests/files/base_conv0.gno
@@ -0,0 +1,27 @@
+package main
+
+func main() {
+	// binary
+	println(0b1010)
+	println(0B1010)
+
+	// decimal
+	println(10)
+
+	// octal
+	println(0o12)
+	println(012)
+
+	// hex
+	println(0xA)
+	println(0xa)
+}
+
+// Output:
+// 10
+// 10
+// 10
+// 10
+// 10
+// 10
+// 10
diff --git a/gnovm/tests/files/base_conv1.gno b/gnovm/tests/files/base_conv1.gno
new file mode 100644
index 00000000000..6ccf8d0fe70
--- /dev/null
+++ b/gnovm/tests/files/base_conv1.gno
@@ -0,0 +1,27 @@
+package main
+
+func main() {
+	// binary
+	println(-0b1010)
+	println(-0B1010)
+
+	// decimal
+	println(-10)
+
+	// octal
+	println(-0o12)
+	println(-012)
+
+	// hex
+	println(-0xA)
+	println(-0xa)
+}
+
+// Output:
+// -10
+// -10
+// -10
+// -10
+// -10
+// -10
+// -10