The basic features of the curved surface helical baffle heat exchanger with special form of baffles was introduced .In the exchanger the fan-shaped baffles fixed with banking angle  α   and backward tilting angle β  are connected by lap with triangular baffle boards.The approximate helicoids are formed at the sides of shell.The peripheries of baffles assume successive helices .The backward tilting structure of similar fan -shaped baffles can reduce counter press caused by ordinary helical baffles to the fluid .The binomial action to pitch is realized by the angles of  α and β  and at the same time the resistance to fluid is reduced which is similar to the partial resistance caused by traditional segmented baffle exchangers when the area of baffle board is large .The curved surface helical baffle heat exchanger with the special form of baffles cuts maximally down the resistance to fluid, enhances heat transfer efficiency and heat transfer coefficient , namely the over -all properties of heat transfer of heat exchanger and resistance , at unit pressure drop , and realizes the aim of saving energy and materials .