Studies on biometry are considered important tools for understanding the germination process of seeds. Moreover, the ex-situ conservation of palm seeds can cause loss of viability over time. The present study aimed to evaluate the biometric characterization and the effect of storage on the seed germination of the Triangle Palm (Dypsis decaryi), a widely used species in Brazilian landscaping. Two independent studies were conducted: I) biometric characterization of diaspores and II) effect of storage in seed germination. For biometry, a sample of 100 diaspores was used and the length, width and thickness were measured. Biometric data were analyzed using descriptive statistics and correlation analysis. The seeds were packed in transparent plastic bags kept in a refrigerator (20 ± 2 ºC and 80% relative humidity) for storage evaluation. The experimental design was entirely randomized. The treatments consisted of six storage periods (0 - control, 30, 60, 90, 120 and 150 days); there were four repetitions and 25 seeds per plot. The germination percentage and germination speed index were evaluated. Diaspores showed little variation in their biometric characteristics, with a mean of 18.39 mm in length, 16.10 mm in width and 15.96 mm in thickness. There was significant and positive correlation between all biometric characteristics. It was observed that germination remained stable until 30 days of storage (90%), with a gradual percentage decrease in later periods. The seed storage allowed to maintain its viability and longevity with the ability to germinate, reaching a germination percentage of 63% after 150 days of storage.