Abstract Introduction: In the world, pneumonia is the first infectious disease which is the leading cause of children under age five morbidity and mortality with 98% of deaths in developing countries. In Ethiopia, child mortality due to pneumonia is the major public health issue. Objective: The general objective of this study was identifying determinant factors that jointly affect the longitudinal measures of pneumonia (respiratory rate, pulse rate and oxygen saturation) and time to recovery of under- five admitted pneumonia patients at Felege Hiwot Comprehensive Specialized Referal Hospital, Bahir Dar, Ethiopia. Method: A prospective cohort study design was used on 101 sampled under-five admitted pneumonia patients from December 2019 to February 2020.The study was conducted using joint model of longitudinal outcomes and survival outcomes. Result: The estimated values of the association parameters for γ_1, γ_2𝑎𝑛𝑑 γ_3 were -0.297,-0.121 and 0.5452 respectively and indicates that; respiratory rate and pulse rate were negatively related with recovery time, whereas oxygen saturation was positively associated with recovery time. As age of patients increased by one month, the average respiratory rate and pulse rate were significantly decreased by 0.3759 bpm and 1.1012 bpm respectively keeping other variables constant, but age has no information about oxygen saturation. Patients at the first birth were 0.284 times less likely to get the chance of recovery compared to patients at the second and above births, keeping other variables constant. Conclusion: Residence, birth order, severity and visit were found as determinants of the longitudinal measures of pneumonia (respiratory rate, pulse rate and Oxygen saturation) and time to recovery of under-five admitted pneumonia patients jointly. The estimated values of variance and covariance were different from zero shows the existence of correlation between rate of change and baseline values between outcomes. To improve child survival, the community should be responsible for post ponding child birth and marriage. Key words: Pneumonia, Respiratory rate, Pulse rate, Oxygen saturation, Joint model