Anestis Delias (Greek: Ανέστης Δελιάς 1912 – 31 July 1944) was a Greek bouzouki player, composer and singer of rebetiko, also known with the nicknames Anestaki (Ανεστάκι) or Artemis (Αρτέμης).
Delias real surname was Delios (Δέλιoς). He was born in Smyrna and had two younger sisters. His father Panagiotis, who was a shoemaker and a noted santuri player, taught him to play the guitar. After the end of the Greco-Turkish war of 1919–1922, Delias and his family moved to Greece and settled at Drapetsona. Having lost his father in the destruction of Smyrna, Delias worked in many different jobs to support his family.
Delias was a very talented musician who by the early 1930s had moved on to play the bouzouki and baglamas. In 1934, together with Yiorgos Batis, Stratos Pagioumtzis and Markos Vamvakaris, he founded the rebetiko quartet, I Tetras i Xakousti tou Peiraios (Greek: Η τετράς η ξακουστή του Πειραιώς, literally Piraeus' famous quartet). This quartet influenced subsequent generations of musicians and composers.
Delias did not produce any recordings during the Metaxas dictator regime that had been established in 1936 since, like many artists of the time, he refused to accept any censoring of his songs. In 1937, he was introduced to heroin by a prostitute and became addicted. He was later convicted of drug use and was expelled to the island of Ios, where in 1938 he met Michalis Genitsaris. When Delias returned to Athens, his friends Pagioumtzis and Bayianteras tried to help him abstain from drugs but without success. Eventually, he increased his daily heroin dose and was unable to perform or work as a result. He was found dead from a heroin overdose on the morning of July 31, 1944. According to other sources, Delias died in 1941. He was the only rebetiko artist to die from drug use.Vamvakaris once said that Delias was "an angel thrown in trash".