Aim The purpose of this study is to determine the efficacy of egg white in maintaining the viability of human periodontal ligament (PDL) cells on avulsed teeth. Methods and Materials The experimental media were: egg white, milk, Hanks’ Balanced Salt Solution (HBSS) as the positive control, and tap water as the negative control. The storage times were 1, 2, 4, 8, and 12 hours. Extracted premolar teeth of healthy individuals were rinsed in the media. After trypsinization and subsequent treatment in collagenase, cell viability was determined using trypan blue staining. The two-way analysis of variance (ANOVA) statistical test was used to compare the results among different media. Results There was no difference in the cell viability between egg white and HBSS media, but there was a statistically significant difference between the viability of PDL cells in egg white medium in comparison with milk (P<0.05) and water (P<0.05). Conclusion Egg white could be suggested as a suitable storage medium. Its principle advantage is its availability. Citation Khademi AA, Saei S, Mohajeri MR, Mirkheshti N, Ghassami F, Torabi nia N, Alavi SA. A New Storage Medium for an Avulsed Tooth. J Contemp Dent Pract 2008 September; (9)6:025-032.