Q. i did three diploma after inter is it possible to do mba and how

I'm afraid not. For, you should be a graduate to do MBA.

If you have working experience of min. 5yrs or more then you have a chance. Many Institutes consider this as eligiblity for MBA.

Hi Surya, I doubt if that is a possibility as the minimum education qualification required to pursue MBA is a Graduate degree from a recognized University and for admission one require to qualify entrances as required by the institutes. You may refer to the following link to know about the institut