BackgroundGlobally, non-communicable diseases (NCD) kill about 40 million people annually, with about three-quarters of the deaths occurring in low- and middle-income countries. This study was carried out to determine the patterns, trends, and causes of in-hospital non-communicable disease (NCD) and injury deaths in Tanzania from 2006–2015.MethodsThis retrospective study involved primary, secondary, tertiary, and specialized hospitals. Death statistics were extracted from inpatient department registers, death registers, and International Classification of Diseases (ICD) report forms. The ICD-10 coding system was used to assign each death to its underlying cause. The analysis determined leading causes by age, sex, annual trend and calculate hospital-based mortality rates.ResultsThirty-nine hospitals were involved in this study. A total of 247,976 deaths (all causes) were reported during the 10-year period. Of the total deaths, 67,711 (27.3%) were due to NCD and injuries. The most (53.4%) affected age group was 15–59 years. Cardio-circulatory diseases (31.9%), cancers (18.6%), chronic respiratory diseases (18.4%), and injuries (17.9%) accounted for the largest proportion (86.8%) of NCD and injuries deaths. The overall 10-year hospital-based age-standardized mortality rate (ASMR) for all NCDs and injuries was 559.9 per 100,000 population. It was higher for males (638.8/100,000) than for females (444.6/100,000). The hospital-based annual ASMR significantly increased from 11.0 in 2006 to 62.8 per 100,000 populations in 2015.ConclusionsThere was a substantial increase in hospital-based ASMR due to NCDs and injuries in Tanzania from 2006 to 2015. Most of the deaths affected the productive young adult group. This burden indicates that families, communities, and the nation at large suffer from premature deaths. The government of Tanzania should invest in early detection and timely management of NCDs and injuries to reduce premature deaths. This should go hand-in-hand with continuous efforts to improve the quality of health data and its utilization.