(Adds details)

June 16 (Reuters) - Wal-Mart Stores Inc said it would buy online men's fashion retailer Bonobos Inc for $310 million in cash, the retailer's fourth e-commerce acquisition in less than a year.

Bonobos' clothes and accessories will be offered on Wal-Mart's Jet.com, the company said in a statement.

Wal-Mart's shares were down about 6 percent at $74.43 in morning trading on Friday, after online rival Amazon.com Inc said it would buy upmarket grocer Whole Foods Market .

The world's biggest retailer has been working aggressively to close the gap with rival Amazon.com Inc under the leadership of Chief Executive Doug McMillon and new e-commerce chief Marc Lore.

Wal-Mart bought online women's fashion retailer ModCloth, outdoor clothing and gear retailer Moosejaw and footwear retailer Shoebuy in the first three months of this year.

The acquisition is expected to close towards the end of the second quarter or the beginning of the third quarter of Wal-Mart's fiscal year ending January 2018, the company said.

Recode had reported in April that Wal-Mart was in advanced discussions to buy Bonobos and that the company had $100 million to $150 million in revenue. (Reporting by Sruthi Ramakrishnan in Bengaluru; Editing by Anil D'Silva)