A direct type backlight module (30) includes a base (21), at least two lamp-fixing units (22) and at least one lamp tube (20). Each lamp-fixing unit is disposed on each corresponding opposite ends of the base. Each lamp-fixing unit includes a bottom board (222) and at least one clip element (224) formed on the bottom board. The lamp tube includes two electrodes defined at two ends thereof and two electrode holders (202) receiving the two electrodes respectively. The electrode holders of the lamp tube are fixed in the corresponding clip elements of the two lamp-fixing units, thus the lamp tube are mounted into the two aligned lamp-fixing units. In the present backlight module, the lamp tubes can be fixed into the clip elements tightly and also easily dissembled from the clip elements of the lamp-fixing units.