Hi
My brother holds a protuguese passport, and want to apply for a portuguese passport, I stay in bahrain, can I apply from bahrain?

Just because your brother qualifies for a Portuguese passport... doesn't mean you do... but you would have to do it from the Portuguese Embassy or Consulate. THey make the determinations based on the proof you have that you are a Portugese citizen....passports are only issued to actual CITIZENS of that country.