The history of the previous ETRS89 system realization in the Republic of Serbia dates back to 1998. Within the EUREF Balkan`98 campaign, GPS measurements were performed in Albania, Bosnia and Herzegovina and Yugoslavia (today Serbia and Montenegro, separated) between September 4th and 9th, 1998 at 29 stations. Among those points, 6 points are located in Serbia. The Serbian part of the EUREF GNSS passive network called YUREF98 was densified in the following years with 838 points from the SREF project which cover the whole country in a 10km grid approximately. The estimated horizontal RMS of the reference points obtained from the SREF network least square adjustment is approximately 1 cm, while the aposteriori RMS height error of SREF points is in the interval of 2-3 cm.