UPDATE 4-Macquarie H1 slides, reassures on capital; shares jump

* H1 profit drops 43 percent

* Gross writedowns A$1.14 billion

* No immediate need to raise cash, shares jump up to 26 pct

* Heading for first full-year profit fall since 1992 (Adds CEO comments, details, updates share price)

By Mette Fraende

SYDNEY, Nov 18 (Reuters) - Macquarie Group, Australia's biggest investment bank, posted a sharp decline in first-half profit and wrote off $750 million from assets, but its shares leapt after it doused fears it needed to raise capital.

The bank, which is heading for its first fall in annual profit in 17 years, had been hammered by investors in recent months as it suffered from a reputation for being an aggressive, expansive bank with market exposure worldwide.

Global investment banks have been punished by investors questioning their high-risk, high-leverage business models following the collapse of Lehman Brothers, which prompted Goldman Sachs and others to become bank holding companies.

Macquarie reported a 43 percent drop in half-year profit, dented by A$1.14 billion in gross asset writedowns, but investors cheered the fact that it did not announce a big share sale to shore up its capital like a number of other banks.

Its shares soared as much as 26 percent at one point to A$26.03, after touching a 6-year low on Monday, as Macquarie indicated it was in no rush to raise capital and was already sitting above the minimum capital requirement.

The stock ended up 16.5 percent at A$24, while the main index dipped 3.6 percent.

"It's a relief. There'd been some concern about an equity raising in the profit announcement today. That didn't eventuate and the numbers were not too far away from forecasts," said Leigh Gardner, head of distribution at ABN AMRO.

Australia's largest lender, National Australia Bank (NAB.AX), said this month it would sell up to A$3 billion in shares to strengthen its balance sheet, prompting analysts to predict others would follow suit as bad debts increase amid the global credit squeeze.

Macquarie, known locally as "the millionnaire factory" as it is said to pay the highest executive salaries in Australia, said its first-half employment expenses were down 48 percent on the previous corresponding period, driven by significantly lower profit share.

Macquarie was vague on any potential job cuts that have swept through the financial industry.

"All those winding back steps that we have taken have all had an impact on jobs already. These initiatives are continuing across the board," Chief Executive Nicholas Moore said after the results announcement.