Abstract: Aiming at the problems of fast rised water cut and rapidly declined production during the development of heavy oil igneous rock reservoirs with bottom water in Bin 674 block of Binnan oilfield,horizontal well development techniques were implemented in 2010.In order to improve the development effects of this reservoir,the plane position,vertical position,horizontal length and development methods of the horizontal wells were optimized through the application of numerical simulation according to the distribution rule of residual oil.Meanwhile,geosteering technique while drilling,foam drilling mud technique,open-hole sieve comple-tion with top cementing and auxiliary wellbore lifting technologies have been applied.The successful development of horizontal wells improved significantly the EOR of the block with daily oil production of 18 t per well and provide us a good reference for the development of similar reservoirs.