HSBC began informing staff in its global banking and markets division in London last week, one of the sources said, with a further round of cuts this week expected to affect around 10 senior people in the unit.
A spokesman for HSBC declined to comment.
The latest round of job cuts at Europe's biggest bank shows new co-chief of global banking Matthew Westerman is making his mark, two of the sources said.
HSBC announced in February that Mr Westerman would be joining from Goldman Sachs to become co-head of global banking in its investment bank, alongside Robin Phillips. The bank announced at the same time it would enlarge the global banking unit by merging its capital financing business into it.
Capital financing, which helped companies raise funds by debt and equity offerings, had become a separate unit under Spencer Lake in a prior reorganisation in 2013.
Its integration back into the banking division has resulted in a number of duplicated and overlapping roles that are now being eliminated to cut costs, the sources said.
HSBC said last June it would slash nearly one in five jobs, as chief executive Stuart Gulliver seeks to combat sluggish growth across the lender's sprawling empire.
Part of that cull involves cutting back risk weighted assets in the investment banking and trading unit of the bank, known as global banking and markets, by up to one third.
© Thomson Reuters 2016