Provided are an end tool of a surgical instrument and a method of manufacturing the same, and more particularly, an end tool of a surgical instrument that may be manually operated to be used in laparoscopic surgery or other various surgery and a method of manufacturing the end tool, wherein a load applied to a pin (rotary shaft) and the pulley is appropriately distributed such that the pulley may be sufficiently rotated and at the same time, an overall durability may be improved.