* HSI up 0.1 pct, HSCE up 0.2 pct, CSI300 up 0.8 pct, SSEC 0.6 pct
* But all indexes head for weekly losses
* Markets may have ended correction period - analysts
SHANGHAI, Nov 21 (Reuters) - Hong Kong and mainland Chinese shares rebounded on Friday as prolonged profit-taking pressure finally eased, but all indexes posted losses on the week despite the highly-touted launch of a landmark link between the Hong Kong and Shanghai exchanges.
Monday's launch of the "stock connect" had been expected to boost share values and volumes on both bourses, but many investors took advantage of the sharp run-up in prices ahead of the debut to take profits instead.
By midday, Hong Kong's Hang Seng Index edged up 0.1 percent to 23,375.06 points after falling for four straight sessions. The China Enterprises Index of top Chinese listings in Hong Kong inched up 0.2 percent.
For the week, the indexes dropped 3.0 percent and 3.3 percent, respectively, with both posting the largest weekly percentage losses since mid March.
The Shanghai Composite Index was up 0.6 percent at 2,466.7 points. The CSI300 index of the largest listed companies in Shanghai and Shenzhen added 0.8 percent.
For the week, the two indexes looked set to fall 0.5 percent and 0.9 percent, respectively.
"Investors are back to being reasonable," said Shih Wenbien, stock strategist at Yunta Securities in Shanghai.
However, mainland China investors' interest in Hong Kong stocks remained weak. They took up less than 1 percent of the daily "southbound" 10.5 billion yuan ($1.71 billion) quota.
Oil companies extended gains in Hong Kong, while the most active stocks were casinos.
Financials sector, particularly brokerages, outperformed.
CITIC Securities Co Ltd rose 3.1 percent, Haitong Securities Co Ltd gained 3.6 percent, and China Merchants Securities Co Ltd climbed 9.7 percent, nearly its 10 percent daily limit-up level.
"The correction is about to end," said Zhang Yanbin, analyst at Zheshang Securities in Shanghai.
"The market will be back to a rising track," he added. "The connect basically closes the bearish market for A-shares and opens the door to a possible bullish run."
Elsewhere, China Railway Construction Corp rose 3.1 percent after state news agency Xinhua reported it has signed a deal worth nearly $12 billion with Nigeria to build a railway along the African nation's coast. ($1=6.1226 Yuan) (Reporting by Shanghai Newsroom; Editing by Kim Coghill)