Injera is staple Ethiopian fermented bread which can be made from different types of cereals,rnparticularly from tef (Eragrostis tef). About two-third of Ethiopian diet consists of injera and itrnaccounts for about two-third of the daily protein intake of Ethiopian population. It has a veryrnhigh nutritional value, as it is rich in calcium and iron. Unfortunately, injera has a short shelfrnlife of 3-4 days essentially due to mould spoilage. The use of weak organic acid asrnpreservatives is allowed in acidic foods, primarily as mould inhibitor. In this study, therninfluence of some commonly used chemical preservatives, benzoic acid, sodium benzoate,rnpotassium sorbate and calcium propionate was investigated by isolation of moulds before andrnduring its ambient storage for 12 days. The preservatives were added immediately beforernbaking at the concentration of 0.1% of benzoic acid/ sodium benzoate, 0.2 % of potassiumrnsorbate, 0.3 % of calcium propionate and 0. 2 % blend of the four (wt/wt) as recommended byrnFood and Drug Administration. Three fungal species: Aspergillus niger, Penicillium sp andrnRhizopus sp found to be responsible in injera spoilage. Penicillium and Rhizopus are morerndominant at the temperature of between 16-200c, while Aspergillus niger is more dominant atrnhigher temperature of between 25-320c. Injera samples had a pH and moisture content of 3.38-rn3.45 and 62-65%, respectively. Antimicrobial activities of the preservatives investigatedrnprolong the shelf life of injera up to12 days. The effectiveness of preservation was ranked asrnsodium benzoate>benzoic acid>potassium sorbate>blend >calcium propionate showing thatrnbenzoates and benzoic acid are the most effective. The incorporation of benzoic acid and itsrnsalt while preparing injera at home or in larger scale processing should be practiced so as tornsave a significant amount of injera that is lost due to mould spoilage.