If I go on Hajj and buy gold in Mecca and sell it in my country I will make much money. Is this practice Halal?

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

Proceeding from your country to perform Hajj while having the intention of Hajj and business is permissible, but the intention of Hajj should be first. Allah Says (what means): {There is no blame upon you for seeking bounty from your Lord [during Hajj].} [Quran 2:198]

The verse refers to the period of Hajj.

Moreover, trading during the Hajj was the practice at the time of the Prophet Muhammad and the rightly guided Caliphs. Above all, this practice has continued till this present time, and no scholar has ever disagreed with it.

No doubt, performing the Hajj for its sake alone is better than performing it with the intention of business.

But, your practice is permissible and there is no harm in doing so.

May Allah bless you, us and all Muslim.

Allah knows best.