The escalating issue of mobile phone addiction (MPA) among college students poses significant risks to their academic performance and psychological well-being. While a growth socioeconomic status (SES) mindset—the belief that SES is malleable—is theorized to promote future-oriented behaviors and enhance self-control, potentially reducing addiction, its specific longitudinal impact on MPA remains unexplored. This study investigated the underlying psychological mechanisms, namely self-esteem and fear of missing out (FoMO), through which a growth SES mindset influences MPA over time. A three-wave longitudinal study with one-year intervals was conducted among 599 undergraduates from four universities in Guangzhou (167 male, 432 female; aged 17-23). At baseline (T1), participants completed measures of SES mindset. Measures of self-esteem and FoMO were administered at the six-month follow-up (T2), and MPA was assessed at the one-year follow-up (T3). Data were analyzed using a cross-lagged panel model in Mplus 8.0, with mediation effects tested via the Bootstrap method in SPSS 27.0. The results revealed that: (1) A growth SES mindset (T1) significantly and negatively predicted MPA (T3) one year later. (2) FoMO (T2) partially mediated the relationship between SES mindset (T1) and MPA (T3). (3) A significant sequential mediation pathway was identified: a growth SES mindset (T1) was associated with higher self-esteem (T2), which subsequently predicted lower FoMO (T2), ultimately leading to reduced MPA (T3). These findings elucidate the longitudinal protective role of a growth SES mindset against MPA, highlighting the chain mediation of self-esteem and FoMO, and provide valuable empirical insights for developing targeted interventions.