In 2001 the Social Democratic Party of Lithuania and the Democratic Labor Party of Lithuania (the ex-Communist Party) completed their formal merger under the name Lithuanian Social Democratic Party and became one of the largest and the most influential political organization in Lithuania. This article aims to examine rate of replacement and social-demographic characteristics of the members of the LSDP National Executive Committee (Presidium) after party completed merger in 2001. The analysis exposed that pace and scope of the LSDP elite replacement was quite intensive between 2001 and 2015. However the rate of survival is greater in the case of founding members, who entered party elite in 2001 than in that of newcomers i.e., who were elected to the Presidium for the first time after 2001. With regard to age of the LSDP elite, dominant member age grouping is 50 years and older. The data indicates that there is a low percentage of female and especially youth in the National Executive Committee.DOI: http://dx.doi.org/10.5755/j01.ppaa.16.1.18013