The Leader of the Socialist Party is the most senior politician within the Socialist Party (Dutch: Socialistische Partij, SP) in the Netherlands. The post is currently held by Lilian Marijnissen, who succeeded Emile Roemer on 13 December 2017.
The Leaders outwardly act as the 'figurehead' and the main representative of the party. Within the party, they must ensure political consensus. At election time the Leader is always the Lijsttrekker (top candidate) of the party list. Outside election time the Leader can serves as the Opposition leader. In the Socialist Party the Leader is always the Parliamentary leader in the House of Representatives.