Sydney Sido Siame (born 7 October 1997) is a Zambian sprinter. He competed in the 200 metres at the 2015 World Championships in Beijing without advancing from the first round. In addition, he won a gold medal at the 2014 Summer Youth Olympics. A run of 9.88 seconds was recorded for the 100 m in Lusaka in 2017, but Siame's time was excluded from the global lists on the basis of doubtful timing. This would have been the first time a Zambian had broken the 10-second barrier and a highly unusual improvement of 0.34 seconds for the athlete.