diff --git a/msgpack/_unpacker.pyx b/msgpack/_unpacker.pyx
index 27facc0a..157291ec 100644
--- a/msgpack/_unpacker.pyx
+++ b/msgpack/_unpacker.pyx
@@ -441,12 +441,17 @@ cdef class Unpacker(object):
         self.buf_tail = tail + _buf_len
 
     cdef read_from_file(self):
+        current_size = self.buf_tail - self.buf_head
         next_bytes = self.file_like_read(
-                min(self.read_size,
-                    self.max_buffer_size - (self.buf_tail - self.buf_head)
-                    ))
+            min(self.read_size, self.max_buffer_size - current_size + 1)
+        )
         if next_bytes:
-            self.append_buffer(PyBytes_AsString(next_bytes), PyBytes_Size(next_bytes))
+            next_bytes_size = PyBytes_Size(next_bytes)
+            if next_bytes_size + current_size > self.max_buffer_size:
+                raise ValueError(
+                    "object exceeds max_buffer_size(%s)" % self.max_buffer_size
+                )
+            self.append_buffer(PyBytes_AsString(next_bytes), next_bytes_size)
         else:
             self.file_like = None
 
diff --git a/test/test_unpack.py b/test/test_unpack.py
index aa4c01f8..c7070763 100644
--- a/test/test_unpack.py
+++ b/test/test_unpack.py
@@ -1,6 +1,6 @@
 from io import BytesIO
 import sys
-from msgpack import Unpacker, packb, OutOfData, ExtType
+from msgpack import Unpacker, pack, packb, OutOfData, ExtType
 from pytest import raises, mark
 
 try:
@@ -90,3 +90,20 @@ def test_unpacker_tell_read_bytes():
         assert obj == unp
         assert pos == unpacker.tell()
         assert unpacker.read_bytes(n) == raw
+
+
+def test_unpacker_raise_max_buffer_size():
+    max_buffer_size = 1024
+    small_value = b"a" * max_buffer_size
+
+    f = BytesIO()
+    pack(small_value, f)
+    f.seek(0)
+    assert list(Unpacker(f, max_buffer_size=max_buffer_size)) == [small_value]
+
+    large_value = b"a" * (max_buffer_size + 1)
+    f = BytesIO()
+    pack(large_value, f)
+    f.seek(0)
+    with raises(ValueError):
+        list(Unpacker(f, max_buffer_size=max_buffer_size))