It follows an exam last year in which the 31-year-old tested positive for a banned substance.
The Jamaican sprinter gave a sample at his national championships, testing positive for the stimulant oxilophrine. His ban has been backdated to June 21, 2013 - the day Powell provided the sample. His ban will end on December 20.
The sanction comes just two days after his former training partner, Sherone Simpson, received an 18-month suspension from the same panel after testing positive for the same substance. Another Jamaican, Olympic discus thrower Allison Randall, has also been given a two-year ban for using diuretic hydrochlorothiazide.
Powell, who missed last year's world championships due to his failed test and will now certainly miss Glasgow 2014, has to wait for the decision to be ratified by the International Association of Athletics Federations.
"This case concerns an international athlete," said Chris Turner, an IAAF spokesman. "The decision of the member federation has to be sent to the IAAF and considered by the doping review board."