you can easily make the z file standard format:

frequency(1) Re(Z(1)) Im(Z(2))

frequency(2) Re(Z(2)) Im(Z(2))

To do this, open your EIS file with in any text editor that supports column mode, such as ultraedit, excel, notepad++, remove all the non-numeric stuff and then save it as a new .z file.

Thank you Dr. Benjamin for you kind answer.

But I think you misunderstand my question or I who misunderstand your answer!

This is my EIS  data file in Excel file and in the same order as you told: 

frequency(1) Re(Z(1)) Im(Z(1))

frequency(2) Re(Z(2)) Im(Z(2))

How can I save it as .z file, this extension doesn't supported by Excel MO.

Could you plz give me more illustrations with this regard?

Thanks

it is easy. There are two ways to do that. First one, you need to convert your file to be .txt format, and then click File->open, select your text file. The second one, you can click File->Past Z Data, and simply copy your data in the excel file and paste it the window it opens. Then, you can process your data now. 

Thanks Dr. Bin.

It is solved