Objective This review aimed at assessing the diagnostic efficacy of contrast-enhanced single-photon emission computed tomography (SPECT) in the diagnosis of mandibular invasion by oral cancers. Methods Five databases were searched electronically on August 5, 2016. The reference lists of included studies were hand searched. Quality assessment was performed by two reviewers in duplicate with tools suggested by Cochrane's handbook. Furthermore, the data extraction of included studies was delivered. Meta-analysis was performed using STATA 11.0. Results Ten studies with 460 participants were included. One study had a low risk of bias, and two studies had a high risk of bias. The remaining seven studies had an unclear risk of bias. Meta-analysis results showed that SPECT had a pooled sensitivity of 0.99 [95% confidence interval=0.87-
1.00]. Sensitivity was 0.99 on Q* point. The specificity of 0.61 and the area under summary receiver operating characteristic curve (SROC) were 0.93 [95% confidence interval=0.90-
0.95]. The pooled positive likelihood ratio was 2.555. The negative likelihood ratio was 0.015. The diagnostic odd ratio was 5.115. Conclusion SPECT had high sensitivity, which became suitable for excluding bone invasion by oral cancers. However, its specificity was relatively low, indicating its limited capability in confirming diagnosis. Therefore, surgeons should perform this method under certain conditions.