Do angels appear in the New Testament?

Yes, about 165 times. One of the most well known angel visitations in the New Testament is when the angel Gabriel appeared before Mary to tell her that she would give birth to Jesus (Luke 1:26-27). Another big event is when angels came to minister to Jesus after the devil tempted Him, after He had fasted for forty days and forty nights. Also when Jesus was in agony praying to the Father in the Garden of Gethsemane, an angel appeared to Him (Luke 22:39-46) shortly before His betrayal by Judas.

In the book of Revelation angels are very involved in assisting the Lord with relaying messages, visions and undertaking pragmatic tasks. Demonic (fallen angels) work with the Antichrist and the false prophet to deceive and harm those left behind in the Rapture. Angels are an important part of the entire Bible in the both Old Testament (referenced at least 108 times) and New Testament.