The purpose of this study was to compare the degree of coherence and efficiency in the discourse production of cognitively healthy middle-old and old-old groups in elderly. Methods: Eleven middle-old (age: 79.00 ± 2.76) and 6 old-old subjects (age: 89.67 ± 3.78) performed three types of discourse tasks. The coherence score and the propositional density were used to compare the degree of topic maintenance and efficiency between two groups. The differences between the groups were assessed using the Mann-Whitney U test. A correlation among the two scores, demographic information, language test results, and the Korean version of the Mini-Mental State Examination (K-MMSE) were also examined. Results: There was a significant difference in propositional density between the two groups. The coherence score correlated with age, K-MMSE, and a confrontation naming test. Conclusion: The results of the present study is significant in that it is the first study to compare the performance of discourse production in the old-old elderly with those of the middle-old elderly. In addition, theme maintenance of normal elderly over 75 years of age is associated with their confrontation naming abilities and overall cognitive abilities.