Abstract: Some physico-viable properties of Eucalyptus citriodora, Eucalyptus camaldulensis and Eucalyptus cloeziana were determined using their seeds in order to provide a suitable test measure for their viability. The bulk densities of E. citriodora, E. camaldulensis and E. cloeziana were found to be 1.18, 1.13 and 1.14 g cm-3 while their germination capacity on volume basis were 25, 94 and 64 seedlings cm-3, respectively. These could be used in calibration of devices for testing of the viability of these seeds as well as predicting their germination. The light transmissivity of E. citriodora, E. camaldulensis and E. cloeziana were found to be 12.17, 2.00 and 2.66 lux, respectively. This property could be applied in identification of viable seeds of Eucalyptus species.