Is a toshiba hard drive compatible with a asus hard drive y/n

You may need to take out any drive cage the ASUS may be using. Have not taken one of those apart, but may laptops use a custom drive cage around the hard-drive. Although the basic SATA connectors and drives are the same size, for the most part, the cages used in the laptop differ.

Also there are two different laptop drive sizes, so things are not 100% guaranteed to fit. 9.5mm and 12.5 mm, so you would want to double check which your laptop can use.
 
The hard drives are compatible (so long as they are both SATA or both IDE). There may be some room for error as some high capacity drives are slightly taller and will not fit in all models... but this is a very rare problem.

As the chipsets are different (or likely different) you will need to do a fresh OS installation when you move the drive, so be sure to back up all files first.