diff --git a/src/make_dafsa.py b/src/make_dafsa.py
index bb308f6..41df88b 100755
--- a/src/make_dafsa.py
+++ b/src/make_dafsa.py
@@ -501,7 +501,7 @@ def parse_psl(infile):
       line = line[1:]
     elif line[0] == '*':
       if line[1] != '.':
-        print 'Unsupported kind of rule (ignored): %s' % line
+        print('Unsupported kind of rule (ignored): %s', line)
         continue
       flags = PSL_FLAG_WILDCARD | PSL_FLAG_PLAIN | section
       line = line[2:]
@@ -536,11 +536,11 @@ def parse_psl(infile):
 
 def usage():
   """Prints the usage"""
-  print 'usage: %s [options] infile outfile' % sys.argv[0]
-  print '  --input-format=psl2c    infile has been generated by libpsl/psl2c utility (default)'
-  print '  --input-format=psl      infile is a Public Suffix List file'
-  print '  --output-format=cxx     Write DAFSA as C/C++ code'
-  print '  --output-format=binary  Write DAFSA binary data'
+  print('usage: %s [options] infile outfile', sys.argv[0])
+  print('  --input-format=psl2c    infile has been generated by libpsl/psl2c utility (default)')
+  print('  --input-format=psl      infile is a Public Suffix List file')
+  print('  --output-format=cxx     Write DAFSA as C/C++ code')
+  print('  --output-format=binary  Write DAFSA binary data')
   exit(1)
 
 
@@ -560,7 +560,7 @@ def main():
       elif value == 'psl2c':
         parser = parse_psl2c
       else:
-        print "Unknown input format '%s'" % value
+        print("Unknown input format '%s'", value)
         return 1
     elif arg.startswith('--output-format='):
       value = arg[16:].lower()
@@ -569,7 +569,7 @@ def main():
       elif value == 'cxx':
         converter = words_to_cxx
       else:
-        print "Unknown output format '%s'" % value
+        print("Unknown output format '%s'", value)
         return 1
     else:
       usage()