Top smartphone maker Samsung Electronics Co. is expected to face challenges in keeping its 20-percent level market share around the globe due mainly to growing rivalry from Chinese firms, a credit appraiser said Monday.

Standard & Poor's said Samsung is set to face challenges as the barriers in the smartphone industry against Chinese firms have weakened.

"These companies, and an increasing number of other smartphone makers, now offer good-quality smartphones at affordable prices, benefiting from cheaper application processors, display panels and other key smartphone components," S&P said.

Accordingly, Samsung is expected to stand in "the middle ground between Apple and the smaller Chinese players," the credit rating agency said.

"While U.S.-based Apple Inc. has kept its reign in the premium smartphone market, S&P expects Chinese manufacturers to keep gaining overall share and increasing revenues, albeit with thin margins," it added.

Samsung took up 21.4 percent of the world's smartphone market in the second quarter of 2015 by shipment, standing as No. 1 player. Its archrival Apple Inc. held 13.9 percent, followed by China-based Huawei with 8.7 percent, the data compiled by industry tracker IDC showed.

S&P added that the smartphone markets in the advanced countries like the United States are expected to remain sluggish over coming years.

Amid such conditions, S&P also said LG Electronics Inc., Samsung's smaller rival, will also face challenges in its efforts to improve profitability. (Yonhap)