In the 2000–01 season, Vassileva was named in Bulgaria's team to the 2001 European Championships in Bratislava, Slovakia. She placed 18th in the short and 15th in the free, resulting in a final placement of 16th. The 2001 World Junior Championships were held in Sofia, Bulgaria. Like a year earlier, Vassileva finished 19th overall, after placing 25th in the short program and 16th in the free. Concluding her season, she progressed past the qualifying round at the 2001 World Championship in Vancouver, British Columbia, Canada, but was eliminated after placing 27th in the short program.