Lastva Grbaljska's population is made up of 51.5% Serbs, which is also the largest ethnic group in Montenegro, and 37.7% Montenegrins while other ethnicities make up only 10.8% of the village's population.
Serbs of Montenegro (Serbian:     / Srbi u Crnoj Gori) or Montenegrin Serbs (c C / crnogorski Srbi), compose the second largest ethnic group in Montenegro (28.7% of country's population), after the Montenegrins. 
