To evaluate the performance of health workers with respect to diagnosis and treatment of acute respiratory infection (ARI) and acute diarrhoea (AD) in children < 5 years in 11 rural heath facilities in Yemen, we carried out a cross-sectional study on 219 cases of ARI and 93 cases of AD. Mean score for performance was 30.04 (range 21–39). The quality of care provided was fair in 89.4% and poor in 4.5% of cases. A “well done” performance of 6.3% was achieved by medical doctors but only 3.6% of medical assistants and 25% of medical assistants scored “poor” for performance, but only 2.5% of medical doctors. Health workers who had received training courses in ARI and AD performed slightly better than those who had not.