Since the reintroduction of plural politics, the Lusaka Central seat has only been won by opposition candidates.
Ms Mwanakatwe beat UPND Candidate Charlotte Scott, who was contesting a seat long held by her husband, Guy Scott.
Meanwhile , the Patriotic Front (PF) is on course to dominating the 156-seat Parliament with at least 87 constituencies secured in Thursday’s elections.
The polls have also seen some hitherto big names failing to win their respective contests while some constituencies have settled for independent candidates.
The PF has scored massive victories in Eastern (15), Luapula (14), Copperbelt (16), Muchinga (10), Northern (12), Central (9) and Lusaka (9) provinces. It has also won one seat each in North-Western and Western provinces.
The United Party for National Development (UPND) has dominated wins in Southern Province, Western Province and North-Western Provinces