MADRID (Reuters) - Swedish fashion retailer H&M is launching a Spanish online store, adding to the competition faced in its home market by Spain's Zara chain, owned by Inditex.

The site will include home decor section H&M Home, just as Zara offers Zara Home.

H&M, which has been slower to launch online versus its rivals, has now invested heavily in its web business and plans sites in eight to 10 markets in 2015, after Spain, Italy and China later this year.

H&M has been gaining market share despite tough competition from discount retailers, especially in Spain where high unemployment has constrained consumer spending.

(Reporting by Elisabeth O'Leary; Editing by David Holmes)