The present invention relates to a nozzle assembly for a vacuum cleaner that has low noise, and is capable of separating off contaminants attached on a cleaning surface. The nozzle assembly (10) includes a nozzle body (20) being in fluid communication with a cleaner body of the vacuum cleaner, including a suction port (22) having suction force applied to; a first and second suction fluid ways (23,24) formed to both sides of the suction port, contaminants-laden air being sucked through the first and second suction fluid way; and a plurality of separating members (30) disposed inside the first and second suction fluid ways, parallel to the first and second suction fluid ways, and inclined top ends thereof pointing to the suction port.