This paper examined the reliability and validity of the State-Trait-Cheerfulness-Inventory (STCI) in Mainland China. The Chinese translation of the STCI-T<106i>, STCI-S<45i> and the Temporal Satisfaction with Life Scale (TSWLS) were administered to 476 university students (313 females, 157 males, 6 missing; 20.40 ± 1.35 years of age). Results showed that the STCI-T<106> and the STCI-S<45> had high Cronbach alphas ranging from 0.60 to 0.92 in Mainland China, and the factorial structures of the instruments were supported. The STCI-T<60> and STCI-S<30> were developed utilizing three criteria for the selection of items. Cronbach alphas were satisfactory ranging from 0.67 to 0.94. The factor structure of the items appeared to be highly generalizable in Mainland China. Joint factor analyses of the state and trait items yielded three factors (cheerfulness, seriousness and bad mood) both as traits and states with the homologous concepts positively correlated. As expected, cheerfulness correlated negatively with bad mood, and cheerfulness correlated negatively with state seriousness. Meanwhile, seriousness correlated positively with bad mood. Moreover, life satisfaction was related positively with cheerfulness and negatively with bad mood, and could be predicted by high cheerfulness and low bad mood. Applications of the STCI-T<60> and STCI-S<30> in the Chinese context and future research are discussed.