Throwing a distance of 17.20m in qualification, Wallader finished third in her qualifying group having thrown the fifth furthest distance overall.
That distance secured her spot in the final, which takes place tomorrow, where she'll be up against fellow Brits Amelia Strickler and Sophie McKinna.
New Zealand's Dame Valerie Adams led the way with a score of 18.52m, a metre ahead of any other competitor.
“Ideally I would have got it done on the first throw but it just took a couple to get it going. But overall I’m happy with that." Wallader said.
“I’m in the final and there are a lot of girls throwing around a similar level so it will be fascinating. Myself and Sophie (McKinna) both have our eyes set on throwing plus 18m so we will see what happens.
“In the last two weeks I’ve had my best sessions in about two years. I’m feeling really positive ahead of the final.”