Elderly has complex changes in the structure and function of the body in the naturally way. Cognitive changes in the elderly due to changes in brain function. Those changes are include a decrease of the ability to solve problems, memory loss, and decreased ability in decision-making in performing daily activities. Based on the background of those problems, this research has purpose to determine the relationship between positive thinking with the ability of memory fungction in the elderly This study uses a correlative analytic design. Population in this study were elderly in Tresna Elderly Social Institution of Budhi Luhur Yogyakarta, Bantul, Yogyakarta. Sample in this research are the elderly who had an age range of 60-70 years consist of 47 people. This study using total sampling method. Variables used in this research are the ability to think positively and the ability of memory in the elderly. Statistic calculation of hypothesis testing using Pearson Correlation test shows the result of the acquisition p value (sig) = 0.000. The p-value (sig) value is less than 0.05, so we can conclude that there is a significant relationship between positive thinking with the ability of memory in the elderly. Results of this study we can conclude that there is a relationship between positive thinking with the ability of memory in the elderly in Social Institutions of Tresna Werdha. Elderly who think positive has better memory score than the elderly with negative thought patterns.