How to Delete Photo Albums on an iPhone
Your iPhone can serve many useful purposes including organizer, to-do list and cellphone. It can also function as a portable photo album. When you sync your iPhone with iTunes, you can add or remove photo albums from iPhoto, the photo-album program bundled with OS X, or you can use any other photo program installed on your computer. Photos take up space, and although it would be easier to just delete a photo album directly from the iPhone without having to connect it to your computer, it is not possible.
Connect the iPhone to your computer using the iPhone's USB cable.
Launch iTunes if it does not open automatically.
Select your iPhone from the "Devices" list in iTunes to open the iPhone's Summary page.
Click the "Photos" tab at the top of the page to show the photo sync options.
Mark the "Sync Photos from" field and select your photo application from the drop-down menu.
Mark the "Selected albums" option to open the "Albums" list. You will see a check next to the albums you have loaded on your iPhone.
Click on the check mark to remove it. Repeat until you have cleared the check marks from all the albums you want to delete from your iPhone.
Click the "Apply" button to start the sync process.
Wait for the sync to finish and then click the "Eject" icon next to your iPhone in the iTunes "Devices" list.
Disconnect your iPhone from the computer.