"I was sick, down with flu and an upper respiratory illness. That's why I pulled out of the Paris Open but now I have recovered," the Russian world number four said on her arrival in Doha on Saturday.
Sharapova's main challenge in the Qatar Open is likely to come from France's world number two Amelie Mauresmo, and fellow Russian Anastasia Myskina, champion in Doha for the last two years.
Sharapova defeated world number one Lindsay Davenport to win the Pan Pacific Open in Tokyo earlier this month after losing to Serena Williams in the semi-finals of the Australian Open in January.
