i-Tail Crop, a unit of the world's biggest maker of tuna Thai Union, set an IPO price range of 30 baht and 32 baht, offering between 600 million and 660 million shares or 22% of the firm.

The final share price would be announced by Nov. 28, Thai Union said in a separate filing on Tuesday.

The IPO would be Thailand's second-largest this year after the $1 billion listing of Thai Life Insurance in July and overtake meat producer Betagro's 17.4 billion baht first time share sale.

The deal comes at a challenging time for Thai equities with the benchmark index down about 2% year to date.

Betagro also saw its share prices slide 9% on its market debut earlier this month.

i-Tail's bookrunners include Credit Suisse, HSBC, Finansia Syrus Securities and Krungthai XSpring Securities.

(Reporting by Chayut Setboonsarng; Editing by Ed Davies)