To determine one-year mortality and associated factors in patients with complex chronic diseases (CCP) in rural health centres and social transformation needs areas in Primary Health Care in Andalusia.Design 1-year longitudinal observational prospective open study.40 health centre.consenting subjects over 18yr according multiple health condition criteria.814 subjects (confidence interval 95%, alpha risk 0.03%, P=.2; 20% of sample increase due to possible losses).1-year mortality.socio-demographic, socio-familial, clinical, functional (Barthel Index, Lawton-Brody Index), cognitive (Pfeiffer Test), prescribed drugs, social healthcare resources consumption, and quality of life (EQ-5D).Interview and computerised clinical history.A total of 832 CCP were included (48.8% women). One-year mortality was 17.8% (n=148). Logistic regression model for mortality included: aged 85 and over, having a caregiver, haemoglobin level less 10g/L, hospital admission in last year, BI under 60 points, and active neoplasia. The calibration obtained from model was good (P=.85 in the Hosmer-Lemeshow goodness-of-fit test), and the discrimination power also good (AUC=0.772 [0.68-0.77] in ROC curve).1-year mortality of CCP in rural centres and social transformation needs areas in Primary Health Care was 17.8%. Knowledge of the factors related to mortality in this group of patients contributes to addressing needs and socio-health resources management.