** Shares of Yunfeng Financial Group 0376.HK drop 15.8% to HK$6.17, on track for the biggest one-day pct decline since August 1

** Stock is the second-biggest pct loser on the Hong Kong bourse

** The insurance and financial services group says it plans sale of 191.3 mln new shares to controlling shareholder Jade Passion, raising HK$1.17 bln ($150.39 mln) for system upgrades, talents recruitment, launch of virtual asset trading services, and for working capital

** The new shares will be sold at HK$6.10 apiece, representing a 16.8% discount to Monday's close of HK$7.33 each

** Says controlling shareholder will buy the new shares following sales of the same amount of existing shares at the same price to third party investors

** YTD, stock up 497.1%, the benchmark Hang Seng Index .HSI up 32.3%

($1 = 7.7797 Hong Kong dollars)

(Reporting by Donny Kwok)

((donny.kwok@thomsonreuters.com))