The vote ended almost six months of political uncertainty after the last year's German federal election saw voters desert the two mainstream parties -- Merkel's Christian Democratic Union (CDU) and the Social Democratic Party (SPD), turning instead to parties on the left and right, the CNN reported.
Merkel will first travel to the residence of German President Frank-Walter Steinmeier in Berlin to be officially nominated before returning to the Bundestag to be sworn in as the Chancellor later on Wednesday.
Last week, the CDU received a boost as the SPD agreed to form a "grand coalition" government with them, ending months of political uncertainty in Germany. The agreement by the SPD guaranteed Merkel a fourth term in office.
The leadership of the SPD had initially ruled out joining Merkel in the government in the wake of historically disappointing results at federal elections in September last year.