Resilience is an important concept in the cancer literature and is a salient indicator of cancer survivorship. The aim of this study is to develop and validate a new resilience instrument that is specific to patients with cancer diagnosis (RS-SC) in Mainland China. First, a resilience framework was constructed for patients with cancer diagnosis. Second, items were formulated based on the framework to reflect different aspects of resilience. Third, two rounds of expert panel discussion were performed to select important and relevant items. Finally, two cross-sectional studies were conducted to evaluate the psychometric properties of this instrument. Fifty-one items were generated based on the resilience framework and the final 25-item RS-SC resulted in a five-factor solution including Generic Elements, Benefit Finding, Support and Coping, Hope for the Future and Meaning for Existence, accounting for 64.72% of the variance. The Cronbach's α of the RS-SC was 0.825 and the test-retest reliability was 0.874. The RS-SC is a brief and specific self-report resilience instrument for Chinese patients with cancer and shows sound psychometric properties in this study. The RS-SC has potential applications in both clinical practice and research with strength-based resiliency interventions.