The Times said Neda Agha-Soltan became a "global symbol of opposition to tyranny" after images of her bleeding to death during the protests in Tehran were shown around the world.
"Ms Soltan, 26, joined the protest because she was outraged at the way that the regime stole the presidential election," the newspaper said on its front page that included a photograph of protesters holding pictures of her.
"She wanted to make a difference, she said. She had no idea quite what an impact she would have. Mobile phone footage of her bleeding to death on a pavement flashed around the world.
"It tore the last shreds of legitimacy from the regime, made her a global symbol of opposition to tyranny, and inspired the Green Movement in a region where populations are all too easily cowed."
Hundreds of thousands of opposition supporters poured into Iranian streets in week-long protests in June over the re-election of President Mahmoud Ahmadinejad, saying the vote was rigged.
The demonstrations were suppressed following a call by supreme leader Ayatollah Ali Khamenei, who gave his strong backing to President Ahmadinejad and warned the opposition against continued street protests.
The opposition movement has continued however to mount protests, with some members wearing the colour green in support of defeated rival presidential candidate Mir Hossein Mousavi.
Iran last month reportedly denounced Oxford University after one of its colleges set up a scholarship in honour of Ms Soltan, accusing it of joining a "politically motivated" campaign.