Abstract: The present disclosure provides an electroencephalogram electrode cap, including: a stretchable covering body; an electrode array; and a fixing seat. The fixing seat includes a fixing structure. The fixing seat is mounted on the stretchable covering body through the fixing structure. The fixing seat further includes a hollow chamber for accommodating conductive medium or conductive medium preform. The electrode array includes plug ends, a plurality of electrode sensing units and a plurality of conductive traces. One end of the conductive trace is connected with the electrode sensing unit, and another end of the conductive trace is connected with the plug end. The electrode sensing unit is connected with the fixing seat.