Objective: The present study evaluated the clinical relevance of an integrative preoperative assessment of inflammation-, nutrition-, and muscle-based markers for patients with muscle-invasive bladder cancer (MIBC) undergoing curative radical cystectomy (RC). Methods: The analysis enrolled 117 patients and the variables included age, body mass index (BMI), neutrophil-to-lymphocyte ratio, monocyte-to-lymphocyte ratio, platelet-to-lymphocyte ratio, modified Glasgow Prognostic Score (mGPS), prognostic nutritional index (PNI), Controlling Nutritional Status score, psoas muscle index (PMI), and peak expiratory flow (PEF). The correlations among the variables were evaluated and their prognostic values after RC were tested. Results: Three inflammation markers (ratios of blood cell counts) were positively correlated (p < 0.0001). The PNI and the BMI were positively correlated (p = 0.04), although they were inversely correlated with the three inflammation markers (p < 0.0001). Age was not significantly correlated with the inflammation markers and PMI, although older age was associated with lower PNI and lower PEF. The disease-specific survival was independently predicted by T4 tumor, positive N status, and decreased PNI. Overall survival was independently predicted by T4 tumor, mGPS, and pretreatment sarcopenia status. Conclusions: The inflammation-, nutrition-, and muscle-based markers would be useful risk assessment tools for MIBC.