My pictures disappeared from my phone are they in iCloud?

Check and see if you have iCloud photo library turned on.

Here is another link for more info

if this is not on your photos are not syncing to iCloud. If it is and you cannot locate your photos and you have a current iCloud backup. This link shows you how to get there and under "Back up Now" it will give you the last time your device backed up or it will tell you why it could not be backed up. If you do not see an error call apple support, get started here, to see what your options are.

Here are some more steps to check

Either way if you want more help your best option would be to verify with an apple representative that you have exhausted all of your resources.

You can login to iCloud at http://www.icloud.com and check to see if your latest photo is there. If you have a lot of photos and have not upgraded your iCloud storage your photos most likely are not all there. Check to see if your storage on your physical device is almost full as well. If you are running IOS 11 you go to Settings > General > About then check your available storage on your device. If all looks good with the storage on your device try resetting all settings, Settings > General > Reset > Reset all settings. This is the top option and will not delete anything on your device but will put everything back to defaults you'll have to reenter in some passwords and set up your Touch ID and background again. DO NOT do the second option the Erase All Content and Settings will delete everything on your device. If that does not work I would schedule an appointment with your nearest apple store.

Did you delete them from the phone? If you go to iCloud.com, are they there in the Photos icon/app?