The 36-year-old will be making her 12th appearance in the last eight at Wimbledon
Venus Williams became the oldest Wimbledon women's quarter-finalist for 22 years as the five-time champion defeated Spanish 12th seed Carla Suarez Navarro 7-6 (7/3), 6-4 on Monday.
Aged 36, Williams is the oldest to make the last eight since 37-year-old Martina Navratilova's run to the final in 1994.
Williams will be making her 12th appearance in the last eight at Wimbledon, and her first since 2010, when she faces Kazakhstan's Yaroslava Shvedova for a place in the semi-finals.
Venus, seeded eighth, was broken twice in the first three games of the first set, but recovered from 3-0 and 5-3 down to win it in a tie-break.
The American legend, who won the last of her seven Grand Slam titles at Wimbledon in 2008, needed just one break to win the second set.
Williams, an eight-time Wimbledon finalist, will be bidding for her first Grand Slam semi-final appearance since the 2010 US Open.