diff --git a/bin/pt-query-digest b/bin/pt-query-digest
index 5d974edf..12bf8097 100755
--- a/bin/pt-query-digest
+++ b/bin/pt-query-digest
@@ -13181,6 +13181,13 @@ sub main {
                if ( $fh ) {
                   PTDEBUG && _d('Reading', $filename);
                   PTDEBUG && _d('File size:', $filesize);
+                  # catch if user is trying to use an uncoverted (raw) binlog  # issue 1377888
+                  if ( $filename &&  $o->get('type')->[0] eq 'binlog') {
+                     if (is_raw_binlog($filename)) {
+                        warn "Binlog file $filename must first be converted to text format using mysqlbinlog";
+                        return 1;
+                     }
+                  }
                   push @read_files, { name => ($filename || "STDIN"), size => $filesize };
 
                   # Read the file offset for --resume.
@@ -14722,6 +14729,14 @@ sub sanitize_event {
    return;
 }
 
+# make an effort to check if file is a raw binlog
+# (i.e. was not converted to text using mysqlbinlog)
+sub is_raw_binlog {
+   my $filename = shift;
+   
+   return -B $filename; 
+}
+
 sub _d {
    my ($package, undef, $line) = caller 0;
    @_ = map { (my $temp = $_) =~ s/\n/\n# /g; $temp; }
@@ -14798,7 +14813,8 @@ server.  Before using this tool, please:
 
 pt-query-digest is a sophisticated but easy to use tool for analyzing
 MySQL queries.  It can analyze queries from MySQL slow, general, and binary
-logs, as well as C<SHOW PROCESSLIST> and MySQL protocol data from tcpdump.
+logs. (Binary logs must first be converted to text, see L<"--type">).
+It can also use C<SHOW PROCESSLIST> and MySQL protocol data from tcpdump.
 By default, the tool reports which queries are the slowest, and therefore
 the most important to optimize.  More complex and custom-tailored reports
 can be created by using options like L<"--group-by">, L<"--filter">, and
@@ -16134,7 +16150,13 @@ The type of input to parse.  The permitted types are
 
 =item binlog
 
-Parse a binary log file.
+Parse a binary log file that has first been converted to text using mysqlbinlog.
+
+For example: 
+
+   mysqlbinlog mysql-bin.000441 > mysql-bin.000441.txt
+
+   pt-query-digest --type binlog mysql-bin.000441.txt
 
 =item genlog
 
diff --git a/t/lib/samples/binlogs/raw_binlog.log b/t/lib/samples/binlogs/raw_binlog.log
new file mode 100644
index 00000000..58bd214d
Binary files /dev/null and b/t/lib/samples/binlogs/raw_binlog.log differ
diff --git a/t/pt-query-digest/binlog_analyses.t b/t/pt-query-digest/binlog_analyses.t
index 26de9308..f8f76016 100644
--- a/t/pt-query-digest/binlog_analyses.t
+++ b/t/pt-query-digest/binlog_analyses.t
@@ -9,7 +9,7 @@ BEGIN {
 use strict;
 use warnings FATAL => 'all';
 use English qw(-no_match_vars);
-use Test::More tests => 3;
+use Test::More tests => 4;
 
 use PerconaTest;
 require "$trunk/bin/pt-query-digest";
@@ -46,6 +46,26 @@ ok(
    'Analysis for binlog011 - Handles 5.6 binlog with checksum CRC32',
 ) or diag($test_diff);
 
+
+
+# #############################################################################
+# Issue 1377888: refuse to parse raw binary log 
+# #############################################################################
+
+my $output = output(
+    sub { pt_query_digest::main(@args, "$trunk/t/lib/samples/binlogs/raw_binlog.log") },
+   stderr => 1
+);
+
+like( 
+   $output,
+   qr/mysqlbinlog/i,
+   'Refuses to parse raw binlog file'
+);
+    
+
+
+
 # #############################################################################
 # Done.
 # #############################################################################