A nail screw, in particular for connecting facade boards or terrace planks made of wood, especially real wood, has a shaft, a conical tip formed at the front end region of the shaft and a head formed at the rear end region of the shaft. A thread has a forward facing insertion flank and a rearward facing grip flank between the conical tip and the head. The thread is a double thread, wherein a grip flank angle (α) measured between the grip flank and a plane perpendicular to the longitudinal axis of the nail screw is between 25 and 35 degrees, more preferably between 28 and 32 degrees, most preferably 30 degrees. The conical tip has a tip angle (ε) between 80 and 120 degrees, more preferably between 90 and 110 degrees, most preferably of 80, 90 or 100 degrees.