Open the iTunes application on your computer.
Select your iPhone from the list of "Devices" on the left side of the iTunes window.
Click the "Photos" tab.
Select the option "Sync Photos From selected folders". Un-check all photo albums that you want to delete from your iPhone. Click the "Apply" button.
Wait for your iPhone to sync with iTunes. When the sync process is complete, iTunes will prompt you that it is safe to remove your iPhone from the iPhone data cable.
If these are albums you created on your phone from photos in Camera Roll, you have to delete all photos from the album before it can be deleted:
- Open the album
- Tap the arrow on top right
- Tap all photos to select them
- Tap Remove at the bottom, and Remove from Album when prompted
- Tap the Albums button at the top
- Tap Edit at the top
- Tap the minus sign to the left of the album, then tap Delete and Delte Album when prompted
- Tap Done