Magnesium aluminate (MgAl₂O₄) spinel powders were prepared by co-precipitation of stoichiometric amounts of magnesium and aluminum chlorides at 80°C. Some sintering aids such as ZnO and MnO₂ were added in the form of chlorides during the precipitation to study their effect on densification. The co-precipitated materials were a mixture of Mg–Al double hydroxide with the presence of few amounts of gibbsite and brucite. After heat-treatment of the precipitated powders up to 1000°C, a crystalline spinel powder was obtained. The presence of 0.5, 1, 2 and 3wt.% of ZnO or MnO₂ as sintering aids increased sinterability after firing up to 1550°C. The highest density was obtained for the samples containing 2wt.% ZnO or 3wt.% MnO₂ which reached about >94 and 96% theoretical density (TD), respectively. The mechanical properties increased by adding ZnO or MnO₂, an exception being the sample containing 0.5wt.% of ZnO for which relatively smaller value were obtained.