diff --git a/base/include/android-base/parseint.h b/base/include/android-base/parseint.h
index 55f1ed3..5bfa47e 100644
--- a/base/include/android-base/parseint.h
+++ b/base/include/android-base/parseint.h
@@ -33,6 +33,14 @@
 template <typename T>
 bool ParseUint(const char* s, T* out, T max = std::numeric_limits<T>::max(),
                bool allow_suffixes = false) {
+  while (isspace(*s)) {
+    s++;
+  }
+
+  if (s[0] == '-') {
+    return false;
+  }
+
   int base = (s[0] == '0' && (s[1] == 'x' || s[1] == 'X')) ? 16 : 10;
   errno = 0;
   char* end;
@@ -79,6 +87,10 @@
 bool ParseInt(const char* s, T* out,
               T min = std::numeric_limits<T>::min(),
               T max = std::numeric_limits<T>::max()) {
+  while (isspace(*s)) {
+    s++;
+  }
+
   int base = (s[0] == '0' && (s[1] == 'x' || s[1] == 'X')) ? 16 : 10;
   errno = 0;
   char* end;
diff --git a/base/parseint_test.cpp b/base/parseint_test.cpp
index 8f9ed77..4afa32e 100644
--- a/base/parseint_test.cpp
+++ b/base/parseint_test.cpp
@@ -25,8 +25,14 @@
 
   ASSERT_TRUE(android::base::ParseInt("123", &i));
   ASSERT_EQ(123, i);
+  i = 0;
+  EXPECT_TRUE(android::base::ParseInt("  123", &i));
+  EXPECT_EQ(123, i);
   ASSERT_TRUE(android::base::ParseInt("-123", &i));
   ASSERT_EQ(-123, i);
+  i = 0;
+  EXPECT_TRUE(android::base::ParseInt("  -123", &i));
+  EXPECT_EQ(-123, i);
 
   short s = 0;
   ASSERT_TRUE(android::base::ParseInt("1234", &s));
@@ -49,7 +55,11 @@
 
   ASSERT_TRUE(android::base::ParseUint("123", &i));
   ASSERT_EQ(123u, i);
+  i = 0u;
+  EXPECT_TRUE(android::base::ParseUint("  123", &i));
+  EXPECT_EQ(123u, i);
   ASSERT_FALSE(android::base::ParseUint("-123", &i));
+  EXPECT_FALSE(android::base::ParseUint("  -123", &i));
 
   unsigned short s = 0u;
   ASSERT_TRUE(android::base::ParseUint("1234", &s));
@@ -63,6 +73,10 @@
   ASSERT_FALSE(android::base::ParseUint<unsigned short>("x", nullptr));
   ASSERT_FALSE(android::base::ParseUint<unsigned short>("123x", nullptr));
   ASSERT_TRUE(android::base::ParseUint<unsigned short>("1234", nullptr));
+
+  unsigned long long int lli;
+  EXPECT_FALSE(android::base::ParseUint("-123", &lli));
+  EXPECT_FALSE(android::base::ParseUint("  -123", &lli));
 }
 
 TEST(parseint, no_implicit_octal) {
@@ -79,10 +93,16 @@
   int i = 0;
   ASSERT_TRUE(android::base::ParseInt("0x123", &i));
   ASSERT_EQ(0x123, i);
+  i = 0;
+  EXPECT_TRUE(android::base::ParseInt("  0x123", &i));
+  EXPECT_EQ(0x123, i);
 
   unsigned int u = 0u;
   ASSERT_TRUE(android::base::ParseUint("0x123", &u));
   ASSERT_EQ(0x123u, u);
+  u = 0u;
+  EXPECT_TRUE(android::base::ParseUint("  0x123", &u));
+  EXPECT_EQ(0x123u, u);
 }
 
 TEST(parseint, string) {