One prominent factor associated with malnutrition is poor appetite. In Japan, the number of older adults living alone has increased annually. Those living alone tended to eat alone, which may lead to poor appetite. This study aimed to investigate the association between eating alone and poor appetite using an index called the Simplified Nutritional Appetite Questionnaire (SNAQ). We surveyed 818 people aged 70 and over in Takashimadaira, Itabashi-ku, Tokyo, Japan, in 2016. Comparisons were made between two groups, a poor appetite group ( = 295) and a good appetite group ( = 523), and results indicate that the poor appetite group had a higher rate of eating alone than the good appetite group (38.0% vs. 20. 1%: < 0.001). Multivariable logistic regression (OR; 95%CI) was performed and poor appetite was significantly associated with the Geriatric Depression Scale (GDS) score (1.707; 1.200-2.427), the number of medications (1.061; 1.007-1.118), JST score (0.894; 0.841-0.950), the indication of "very healthy" on a self-rated health scale (0.343; 0.152-0.774), and reports of eating alone (1.751; 1.130-2.712). Our results suggest that eating alone is associated with a poor appetite.