Yes—and no. We call the seventh day of the week "Saturday," but we follow the Roman method of counting our days from midnight to midnight. The biblical seventh day runs from sunset on Friday evening to sunset on Saturday evening.
Notice Genesis 1:5: "God called the light Day, and the darkness He called Night. So the evening and the morning were the first day." This verse tells us how God counts the period of time we call a "day." A full day consists of the evening, or dark portion, and a morning, or light portion. It begins with the onset of evening—sunset—and runs its 24-hour course to the following sunset.
We see how this applies to a Sabbath-day from Leviticus 23:32, which specifically refers to the annual holy day of Atonement (Yom Kippur): "It shall be to you a sabbath of solemn rest, and you shall afflict your souls; on the ninth day of the month at evening, from evening to evening, you shall celebrate your sabbath." Earlier, God commanded Atonement to be observed on the tenth day of the seventh month (verse 27). Verse 32 clarifies that the tenth day begins when the ninth day ends at evening. All other Sabbaths, weekly and annual, also run from sunset to sunset.
In the New Testament, the practice is continued. Mark 1:21-31 shows Jesus keeping the Sabbath in the synagogue in Capernaum. In fear of breaking the Sabbath (but see Matthew 12:9-14), the people waited until after the sun had set to bring the sick and demon-possessed to Him for healing (verse 32).
In another example, Luke 23:50-56 records that, as the evening of the Sabbath approached, Joseph of Arimathea hurried to place Jesus' body in the tomb. Jesus died at the ninth hour of the day (about 3 pm; verses 44-47), so Joseph had only a few hours of daylight remaining to do all his work before the sun set (see also Mark 15:42-47).