Question Summary:
Is it a Sunnah to use frankincense?

Question Detail:

is frankincense or thyme from the sunnah? somebody told me they used to use frankincense in the prophet (saw) time to keep jinns away? is this true 

Answer :

In the Name of Allah, the Most Gracious, the Most Merciful.
As-salāmu ‘alaykum wa-rahmatullāhi wa-barakātuh.
‘Allāmah Ibn Al Qayyim rahimahuAllah said:
Though it has been reported regarding frankincense that Nabi salla Allahu ‘alaihi wa sallam said, “Perfume your homes with frankincense and thymus”, it is unauthentic. However, it has been reported from ‘Ali radiAllahu ‘anhu that he said to a man who complained of being forgetful, “Use frankincense, for it heartens one and rids forgetfulness.”[1]
We are unaware of the correlation between frankincense and jinns. In any case, recitation of Surah Al Falaq (Surah #113) and Surah Al Nās (Surah #114) are sufficient to repel any such evil.
And Allah Ta’āla Knows Best
Hisham Dawood
Student Darul Iftaa
Chicago, USA 
Checked and Approved by,
Mufti Ebrahim Desai.