What is the best time of year to visit in Mongolia? [closed]

Depends on your interpretation of "right time".

Do you mean the driest / wettest season (if there is such a thing in Mongolia) ?

Do you mean where there are festivals and events happening ? Obviously you would go when they are happening if that's what you want to see.

Do you mean when there are less other tourists to compete with for accommodation ?

Perhaps you could get hold of a travel guide such as e.g., "Lonely Planet", "Rough Guides", etc. I dare say one of them would have 'recommendations' for favourable times of the year for what you want to do and see there.

Or maybe search for a website from Google, such as MONGOLIATOURISM at www.mongoliatourism.info/