Abstract: Boiling heat transfer has many advantages such as low temperature difference of heat transfer and high heat transfer coefficient. It has great significance to improve equipment’s compactness, economics and security. At present, smooth tubes are still widely used as boiling components in nuclear power plant; there is great extension to improve the boiling heat transfer coefficient. In this paper, water was used as boiling medium, and the boiling heat transfer characteristics of smooth tube and three other kinds of enhanced tubes including integral pin-fin tube, porous surface tube and winded pin-fin tube were studied experimentally. On the base of the experimental investigation, the enhanced mechanisms of the enhanced tubes were analyzed. There are large mounts of three-dimensional pin-fin on the surface of integral pin-fin tube which can significantly increase the heat transfer area and prevent bubbles coalition surrounding the tube. The porous tube is fabricated by forming numerous of micro-cavities on the surface of smooth tube, and the amount of embryo nucleus and the bubble growth frequency both greatly increase, so the boiling heat transfer enhances obviously. The winded pin-fin tube is a composite enhancement tube which has the advantage of integral pin-fin tube and porous tube and it has relatively high enhancement capability.