diff --git a/sync.py b/sync.py
new file mode 100644
index 0000000..88ff089
--- /dev/null
+++ b/sync.py
@@ -0,0 +1,111 @@
+# PDF Sync Manager
+# Created by Kiritow.
+
+import platform
+import os
+from hashlib import md5
+from ftplib import FTP
+
+def ScanPDF(root_dir):
+    lst=[]
+    for parent,dirs,files in os.walk(root_dir):
+        for file in files:
+            if(file.endswith(".pdf")):
+                lst.append([file,os.path.join(parent,file)])
+    return lst
+
+def GetMD5(filename):
+    f=open(filename,'rb')
+    h=md5()
+    while True:
+        b=f.read(4096)
+        if not b:
+            break
+        h.update(b)
+    f.close()
+    return h.hexdigest()
+
+def CheckPDF(lst):
+    clst=[]
+    flst=[]
+    for pr in lst:
+        m=GetMD5(pr[1])
+        if(m in clst):
+            print('md5 same: ' + pr[0])
+        else:
+            clst.append(m)
+            flst.append([pr[0],pr[1],m])
+    return flst
+
+def SyncPDF(uinfo,lst):
+    ftp=FTP(uinfo[0])
+    ftp.encoding='UTF-8'
+    ftp.login(uinfo[1],uinfo[2])
+    ftp.cwd('/md5')
+    mlst=ftp.nlst()
+    tlst=[]
+    upsz=0
+    tmpid=0
+    for name,addr,check in lst:
+        tmpid=tmpid+1
+        if(check not in mlst):
+            print('[' + str(tmpid) + '][Untracked] ' + name)
+            tlst.append([name,addr,check])
+            upsz+=os.path.getsize(addr)
+        else:
+            print('[' + str(tmpid) + '][Synced] ' + name)
+
+    lsz=len(tlst)
+    if(lsz<1):
+        print('Nothing to upload.')
+        return
+
+    print("Totoally " + str(lsz) + " files need to upload. Need to upload: " + str(round(upsz/1024/1024,2)) + 'MB')
+    choice=input('Are you sure to upload? (Y/N): ')
+    if(choice!='Y'):
+        print('Aborted.')
+        return
+
+    ftp.cwd('/')
+    fnlst=ftp.nlst()
+
+    donesz=0
+    for i in range(lsz):
+        print('[' + str(i+1) + '/' + str(lsz) + '][Uploading] ' + tlst[i][0])
+        remote_filename=tlst[i][0]
+        while(remote_filename in fnlst):
+            remote_filename=remote_filename.replace(".pdf","_.pdf",1)
+        with open(tlst[i][1],'rb') as fp:
+            file_size=round(os.path.getsize(tlst[i][1])/1024/1024,2)
+            donesz+=os.path.getsize(tlst[i][1])
+            print('file size: ' + str(file_size) + 'MB')
+            ftp.storbinary('STOR '+remote_filename,fp)
+            print(str(round(donesz/1024/1024,2)) 
+                    + "MB uploaded. ("
+                    + str(round(donesz/upsz*100,2))
+                    + '%)' )
+
+            # MD5 file content must be utf-8
+            with open(tlst[i][2],'w',encoding='utf-8') as cf:
+                cf.write(remote_filename)
+            with open(tlst[i][2],'rb') as cf:
+                ftp.storbinary('STOR /md5/'+tlst[i][2],cf)
+            print('Check file ' + tlst[i][2] + ' updated.')
+            os.remove(tlst[i][2])
+
+def FetchInfo():
+    svaddr=input('Server Addr:')
+    uname=input('FTP Username:')
+    upass=input('FTP Password:')
+    return (svaddr,uname,upass)
+
+# Main Program
+print("""PDF Sync Manager
+Author: Kiritow""")
+search_dir=input('Where should we start? :')
+print ('Scanning...')
+cl=CheckPDF(ScanPDF(search_dir))
+print ('Syncing...')
+uinfo=FetchInfo()
+SyncPDF(uinfo,cl)
+