on your Phone. Go to the system settings and open Developer options then check on USB debugging option ( If your phone have Android 4.2 or upper version then first enable Developer options here is guide of this
).
Now go to system setting then open Security tab and scroll down and find Unknown Source option, tick the checkbox for enable this (see in image 2). After then Download and install Root App
Step 3: Open application menu in your phone then find and open Kingroot app. Now you will see a big green circle, tap on it (see in image 4). It is taking 1-2 min to rot your phone after then you will see a green right symbol (see in image 5). That’s all, reboot your phone. Now your phone is rooted. If you want to check your Mobile rooted or not try this app
Root checker.
Method 4 Rooting A8 with Frama Root :1-Download
Frama Root App From
Here To your lap or pc .
2-Make sure you have downloaded and installed the required
driver on your PC From
Here .
3-Make sure there is at least 80% battery left on your smartphone before begin
rooting your device.
4-Go to Settings > Security > Make sure you have checked on the Unknown Sources checkbox.
5-Back up the
Samsung Galaxy A8 From
here .6-Connect the
Samsung Galaxy A8 to your PC using an appropriate USB cable.
7-Copy and paste the Framaroot apk from your PC over to the
root of your device’s SD card.
8-Open the file explorer app ( if you don’t have one on your device, then you may want to download 9-either Astro
File Manager / ES File Explorer ) and install the Framaroot apk by tapping on its icon.
10-Open the
Framaroot app on your Samsung Galaxy A8
11-From the
Framaroot app, select Install Superuser under the Select an action to execute after rootsection.
12-From the Select an exploit section, select the Boromir exploit. ( You can try Faramir orBarahirexploit if Boromir doesn’t work ).
13-You should see a pop-up like the one above after you’re done.
Reboot your device.
14-Congratulation! You’ve just Rooted
Samsung Galaxy A8!
Source : geekwarning.com, This Blog, And web