Why you need to transfer music from iPhone to iTunes?
yes, always happened like this:

The computer crashed and now it has reached a new you want to transfer all the music from your iPhone to computer before you sync again.

Just get a new laptop and want to transfer all songs and playlists from my iPhone to my iTunes library.

By the way, you do not want to lose anything on your iPhone, when you sync your music back to iTunes. Keep it simple, we call it iPhone backup.

But keep in mind in order to protect copyrighted music, iTunes block in which the transfer of music and song back to iTunes. All you can do is sync, is almost certain to lose something on your iPhone.

Any best way to transfer music from iPhone to iTunes without deleting the music on the iPhone or iTunes?

In fact, you just follow these steps:

Step 1: Download the iPhone to PC Transfer.
Step 2: Change how-Sync synchronization manually before connecting to iTunes.
Step 3: Running iPhone to PC transfer and transfer all the music you want to add iTunes to your first team. This tool does not erase everything on your iPhone or iTunes.
Step 4: Add music to your computer with iTunes.

Pretty easy, right?

Just do it!
The best tool for you:

Transfer music from iPhone to iTunes for Windows System

Transfer music from iPhone to iTunes for Mac OS X

How To Copyright a Song : Music Copyright Forms