Can permanent residents get USA travel passport??

if you're already permanent resident you already have your country passport that is sufficient fro traveling make sure of any visa requirements though

A legal permanent resident of the US may be eligible to apply for a USCIS Travel Document, but not a US passport. The Travel Document can be used for international travel if the holder is not in possession of a passport from his/her own country, and if the government of the foreign country authorizes its use.

http://www.uscis.gov/portal/site/uscis/menuitem.5af9bb95919f35e66f614176543f6d1a/?vgnextoid=17be96981298d010VgnVCM10000048f3d6a1RCR D&vgnextchannel=828807b03d92b010VgnVCM10000045f3d6 a1RCRD

Permanent Residents usually travel on their respective country's passport.

However if you become a Permanent Resident through a Refugee or Asylee status, then you have to apply for a Refugee Travel Document. A refugee travel document looks just like the American Passport, but it has a different color and is issued by the US Department of Justice. The refugee travel document has a one year validity and must be returned back to the Immigration Services after coming back to the US.

Travel documents are also given to foreign nationals who want to travel, but cannot get a passport from their country of nationality.

It would be better for you to travel on the passport issued by your country of citizenship. US travel documents for permanent residents are mostly used by refugees and stateless persons.