Zhang collected her 19th win in her last 23 matches in taking her second career WTA title. She won the Guangzhou International Women's Open, also in her native China, in September.
Morita fought off seven match points in her second-round match and another in the quarterfinals before advancing to the title match with a straight-set win Saturday. But she couldn't overcome an injury to her left hamstring and conceded the match to Zhang after the first set.
Zhang won the set by finishing off both of her break chances but the play had been fairly even until Morita's injury.
Zhang, 2-0 in WTA finals, picked up $20,000 along with the championship. Morita, who won $11,000 Sunday, fell to 0-3 in championship matches. She lost finals at the Thailand Open in 2007 and at the Japan Open in 2008.
Swim Week Miami Beach 2014 [PHOTOS]