diff --git a/lib/function/arithmetic/pow.js b/lib/function/arithmetic/pow.js
index e64ccffca..6142d9f57 100644
--- a/lib/function/arithmetic/pow.js
+++ b/lib/function/arithmetic/pow.js
@@ -81,7 +81,7 @@ module.exports = function (math) {
       }
 
       if (y instanceof BigNumber) {
-        if (y.isInteger() && !x.isNegative()) {
+        if (y.isInteger() || !x.isNegative()) {
           return x.pow(y);
         }
         else {
diff --git a/test/function/arithmetic/pow.test.js b/test/function/arithmetic/pow.test.js
index 5e3b3fa83..f61cb2047 100644
--- a/test/function/arithmetic/pow.test.js
+++ b/test/function/arithmetic/pow.test.js
@@ -50,6 +50,9 @@ describe('pow', function() {
   it('should exponentiate bignumbers', function() {
     assert.deepEqual(pow(bignumber(2), bignumber(3)), bignumber(8));
     assert.deepEqual(pow(bignumber(100), bignumber(500)), bignumber('1e1000'));
+
+    assert.deepEqual(pow(bignumber(-1), bignumber(2)), bignumber('1'));
+    assert.deepEqual(pow(bignumber(2), bignumber(1.5)), bignumber('2.828427124746190097603377448419396157139343750753896146353359476'));
   });
 
   it('should exponentiate a negative bignumber to a non-integer power', function() {