A nuclear radiation detection system includes a detector for detecting the nuclear radiation, an amplifier for amplifying electric signals generated by the detector, and a PCB (printed circuit board) comprising a first circuit board which is flexible and is used for transmitting electric signals as well as provided with a plurality of first conducting layers inside; two second circuit boards respectively arranged on the two ends of the first circuit board and provided with a plurality of second conducting layers corresponding to the first conducting layers inside; and a plurality of through holes, each through hole being communicated with one first conducting layer and one second conducting layer, so as to realize electrical connection between the first conducting layer and the second conducting layer by a third conducting layer which is arranged in a plated manner on the inner surface of the through hole. A connection terminal of the detector is inserted into some through holes at one end of the PCB, and the connection terminal of the amplifier is inserted into the other through holes at the other end of the PCB, thereby transmitting the electric signals generated by the detector to the amplifier through the PCB.