Background: A nutritional problem, especially under nutrition is one of the common public health problems in elderly causing greater mortality and economic loss in developing countries.

Objectives: to assess the nutritional status and predictors of malnutrition among elderly (> = 65 years) residing in Eastern Ethiopia, 2019.

Methods: Community based cross sectional study was conducted among randomly selected 630 elderly selected by multistage sampling in Eastern Ethiopia. Nutritional status was screened by Mini Nutritional Assessment tool to classify as malnourished (MNA < 17), at risk of malnutrition (MNA from 17 - 23.5) and normal (MNA >23.5). Geriatric depression scale short form was used to assess the depression level. Well trained health graduate students collect the data.  Ordinary logistic regression with proportional odds was done with odds ratio, coefficient at 95% Confidence interval. Level of statistical significance was declared at P value less than 5%.

Results: majority, 306 (51.7%) and 93 (15.7%) at risk of malnutrition and malnourished. Having depression (χ2=106.02; p-value = 0.0001), with chronic pain (χ2 = 67.1; p-value= 0.0001), and health insurance (χ2 = 34.6; p-value = 0.000) were predictors of malnutrition. Elderly people who are user of pension fee had 1.37 times higher odds to be malnourished as compared to those who are not (AOR=1.37; 95% CI; 0.91-2.05). Similarly, those who are working currently had lower odds of being malnutrition by 27% (AOR= 0.73; 95% I; 0.48-1.12). I addition, those rural area had higher odds of malnutrition ((AOR= 0.52; 95% I; 0.32-0.82). Those elderly who had potential to cover their expense (AOR= 0.73; 95% I; 0.49-1.11) and with health insurance (AOR= 0.57; 95% I; 0.35-0.94) had lower odds of malnutrition as compared to their counterparts. Furthermore, having chronic pain (AOR = 1.97; 95% I; 1.34 - 2.91), previous hospitalization (AOR = 1.67; 95% I; 1.12 - 2.49) and depression (AOR= 4.17; 95% I; 2.76-6.31) were positive predictor of malnutrition.

Conclusions: khat chewing, presence of health insurance, chronic pain, insomnia and depression were important predictors of malnutrition among elderly.

Implications: malnutrition is major public health problem in the area, even if it is not given due attention. The national Ministry of health should give essential emphasis on this population and should have better guideline for caring elderly.

Keywords: mini nutritional assessment; malnutrition; elderly; ordinal logistic regression; Ethiopia.