Background: The mutated Anaplastic lymphoma kinase (ALK) gene has been identified as a potential and major predisposition oncogene in human neuroblastomas (NBLs). However, the frequency of mutation is only 5-8%. Purpose: The present study was performed to determine the level of ALK mRNA gene expression in primary neuroblastoma and to assess its relation to other prognostic factors of neuroblastoma. Methods: Quantitative real-time RT-PCR was applied to examine the expression level of ALK mRNA in seventy-nine primary neuroblastoma patients, and its prognostic value in those patients. Immunohistochemical staining was used to check the expression level of ALK proteins. Results:In analysis of 79 patients with sporadic primary neuroblastoma, we found that high expression level of ALK mRNA was significantly associated with Shimada’s pathological classification (p<0.001), patient’s age (p<0.001), MYCN amplification status (p<0.001), tumor stage (p<0.001) and low TrkA expression level (p=0.0390), all these factors are known to be associated with poor prognosis in neuroblastoma. Of interest, immunohistochemical study revealed positive ALKin ALK-amplified tissues. Furthermore, mutation results showed that ALK mutation represented about4.6% of cases and ALK amplification represented about 1.5% of cases. So that mutations not only occur among unfavorable cases with low ALK but also in favorable cases with high ALK expression. Conclusion: Our findings suggested that high expression of ALK gene is associated with poor prognosis of NBL so it can be used as a prognostic factor in NB in clinical practice.