Google will pay its new chief financial officer, Ruth Porat, more than $70m.

Porat, who is joining Google from Morgan Stanley, will get an instant $5m cash signing-on bonus, $25m worth of Google shares and a further $40m in “biennial” stock awards. Her actual base salary will be $650,000.

She will have to stay at the company for four years to be sure to collect all the money.

It is a big jump in pay from the roughly $10m a year she has collected as Morgan Stanley’s chief financial officer.

Porat is the latest in a recent flurry of Wall Street types decamping to Silicon Valley – and collecting a lot more money on the way. Twitter gave Anthony Noto, its new chief financial officer, $61m worth of shares to join the company from Goldman Sachs.

Porat, who has been at Morgan Stanley since 1987 and advised the US government on its rescue of Fannie Mae and Freddie Mac during the 2008 financial crisis, is often referred to as “the most powerful woman on Wall Street”.

She will join Google on 26 May, and report directly to Google’s chief executive and co-founder, Larry Page.

“We’re tremendously fortunate to have found such a creative, experienced and operationally strong executive,” Page said in a Google blogpost announcing her appointment on Tuesday.

Porat said she “can’t wait to roll up my sleeves and get started … I’m delighted to be returning to my California roots and joining Google. Growing up in Silicon Valley, during my time at Morgan Stanley and as a member of Stanford’s board, I’ve had the opportunity to experience first-hand how tech companies can help people in their daily lives.”

Porat has spent 28 years at Morgan Stanley, during which time she led the bank’s team raising funds for Amazon, eBay and Netscape during the dotcom boom. When the bubble burst, she reinvented herself as a financial services banker.

She rose to nationwide prominence advising the US Treasury on the collapse of insurer AIG and the bailout of mortgage providers Fannie Mae and Freddie Mac. She features in the 2011 film Too Big to Fail, in which she is played by Jennifer Van Dyck.