Healthcare system in Nigeria is constantly facing several issues due to inadequate personnel or professionals to mount the facilities and attend to both in-patients and outpatients at various levels of healthcare system, ranging from primary, secondary and tertiary levels of healthcare across Nigeria in general and South-South in particular. This inadequate healthcare professionals have led to the decaying of facilities thus placing the healthcare system in a moribund state creating room for patient’s apathy. This study is aim to evaluate the Effects of Brain Drain on Health Care System in South-South Nigeria. This was a cross-sectional study involving 350 (final year medical students 200 and house officers 150). A well-structured questionnaire was administered to participants. The study lasted for a period of 2 months. Statistical analysis was done using SPSS version 25.0 and p < 0.05 was significant. The results revealed that 85.7% of the participants agreed that brain drain actually affects healthcare system, 97.1% was due to shortage of manpower, 94.3% agreed it affects patients, 71.4% affects revenue generation, 71.4% agreed BD increases quackery, 85.7% of them said it led to over labour, and 71.4% agreed that affects the economy. The study shows inadequate healthcare professionals as a result of brain drain has ruined our healthcare system and this have affected the revenue generation, training and re-training of healthcare personnel as well as contributing to patient’s apathy towards patronizing the healthcare facilities.