This research investigated the relationship between smartphone addiction (SA) and autism quotient, considering the indirect effect of theory of mind (ToM). This research successfully recruited 399 smartphone users to complete self-reported measures for SA, ToM, and autism quotient. Initial results with Pearson's correlation revealed a significant negative relationship between excessive smartphone use and ToM. A significant negative correlation was observed between ToM and the gauged autism quotient. However, the measured SA did not correlate significantly with the autism quotient. From the path analysis, the measured SA did not predict autism quotient and ToM significantly, whereas the measured ToM significantly predicted autism quotient. The negative relationship supports that individuals with established ToM are less likely to develop characteristics of autism. The estimated indirect effect was not significant, implying that ToM did not mediate the direct effect of SA on autism quotient. Implications and limitations are further discussed in this manuscript.