The BBC`s Jonah Fisher in Yangon says her comment was her strongest assertion yet that she intends to govern anyway.
The elections will be Myanmar`s first openly contested polls in 25 years.
More than 90 parties are standing in the first national elections since a nominally civilian government took power in 2011.
Ms Suu Kyi told the news conference in Yangon, her last before polls open: "I will be above the president. It`s a very simple message."
She said there was nothing in the constitution which prevented this.
Clause 58 in Myanmar`s constitution, however, states that the president "takes precedence over all other persons" in the country.
Ms Suu Kyi cannot be president herself as her sons hold British passports.
Ms Suu Kyi criticised the electoral process so far, saying it had been less than totally free and fair and that the electoral commission had failed to deal with irregularities.
She also briefly touched on the Rohingya, the persecuted mostly Muslim minority who Myanmar says are not citizens and who do not have a vote.
Ms Suu Kyi has been criticised for not speaking out on the issue, but in her news conference, she said the situation should not be exaggerated.
The constitution of Myanmar, also known as Burma, grants the military at least 25% of parliamentary seats.
The NLD and any allies will need to win at least two-thirds of the remaining seats in order to choose the next president.
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