Objective To summarize our experience on medical observation and treatment of 32 cases with suspected or probable Ebola virus disease (EVD) under level 4 personnel bio-protective condition in Liberia. Methods A total 32 suspected or probable EVD cases admitted in China Ebola Treatment Unit (ETU) in Liberia during January 14, 2015 to March 14 were included in the present study. The doctors made the ward rounds under level 4 personal bio-protective conditions. They were diagnosed by inquiring the detailed history and performing partial physical examination, and were given dihydroartemisinin piperaquine phosphate tablets (3 tablets, 1/d), levofloxacin (0.5 g, 1/d), centrum (1 tablet, 1/d), oral rehydration salt Ⅲ(2 bags, 3/d), and nutrients (40 g, 3/d) as basic treatments initially combined with supportive medication, which was aimed to relieve their symptoms. The clinical data, including the epidemiologic history, clinical symptoms and signs, diagnosis, treatment efficiency and adverse effects were retrospectively analyzed. Results The mean age of the 32 patients was (40.53±13.89) years old(ranging 14-83), with 22 males and 10 females. The average time after the onset of illness was 4.5(1-30)d. All the patients had fever, with the average maximum temperature being (38.36±1.01)℃. The main symptoms included fatigue in 25 cases (78.12%), joint/muscle pain in 22 patients (68.75%), nausea/vomiting in 17 cases (53.12%), headache in 16 cases (50.00%), anorexia/loss of appetite in 15 cases (46.88%), diarrhea in 14 cases (43.75%), abdominal pain in 14 cases (43.75%), cough in 12 cases (37.50%), chest pain in 10 cases (31.25%), dyspnea in 5 cases (15.62%), dysphagia in 4 cases (12.50%), hiccup in 3 cases (9.38%), and gastrointestinal hemorrhage in 2 cases (6.25%). The mean time of hospitalization was (3.94±2.29) d. The final clinical diagnosis were: acute gastroenteritis in 13 cases, acute respiratory tract infection in 7 cases, upper gastrointestinal bleeding in 1 case, ascites of unknown cause (suspected hepatoma) in 1 case, jaundice of unknown cause in 1 case, asthma exacerbation in 1 case, malaria in 1 case, and incomplete intestinal obstruction in 1 case. Twenty-six cases were discharged and 6 cases died, showing an improvement rate of 81.25%(26/32). The temperature restored the normal level in 23 cases and the mean time it took was (3.51±1.60) d. The treatment was tolerable and there were no severe side effects. Conclusion Close medical observation, professional inquiry and physical examination are important methods to make clinical diagnosis for suspected Ebola cases in ETU. Empiric therapy with oral drugs combined with supportive therapy is safe and effective for suspected or probable EVD patients in Liberia.