Cody Haevischer and Matthew Johnston were each convicted of conspiracy and six counts of first-degree murder, for which they received mandatory life sentences with no parole for 25 years.
A judge concluded Haevischer, Johnston and another man shot six people in a high-rise condo unit in Surrey, B.C., in October 2007.
The Crown's theory at trial was that the Red Scorpions gang plotted to murder a rival drug trafficker, but that five others, including an unwitting neighbour and a fireplace repairman, were also killed to eliminate witnesses.
Neil Mackenzie, a spokesman for the criminal justice branch, says both men filed their conviction appeals in the B.C. Court of Appeal on Thursday.
Alleged gang leader Jamie Bacon is awaiting trial, while gang leader Michael Le pleaded guilty to conspiracy midway through Haevischer and Johnston's trial.