After Masafumi IKENOBO, the husband of her eldest daughter Yuki, who formerly worked as a government official in the Finance Ministry, was defeated in an election, Yasuko IKENOBO was requested by the then New Frontier Party to run as a candidate for a proportional representation election (ranked first on the list of candidates) and she was elected as a representative for the first time in 1996 in the 41st general election of the members of the House of Representatives.
選挙には長女・由紀の夫で元大蔵省官僚の池坊雅史が出馬した（落選）ことから、当時の新進党から比例代表制（名簿1位）からの出馬要請があり、1996年の第41回衆議院議員総選挙で初当選。