On a 10-point scale where 10 is the best score, Grybauskaitė, whose second term in office will end next year, was given 7.94 for her overall performance as president.
The president scored 7.42 for her foreign policy, according to the poll carried out by Spinter Tyrimai on June 19 to 27.
Those polled were asked what impact Grybauskaitė's email exchange with Eligijus Masiulis, a former Liberal Movement leader on trial in a political corruption case, had on their opinion of the president.
Some 26.9 percent of respondents said this had a negative effect and 6.7 percent said that their opinion improved. Another 51.3 percent said their opinion remained unchanged and 15.1 percent had no opinion.