There was no immediate comment from Palestinian officials about the incident, which took place at the Qalandiya crossing near the city of Ramallah.
Police said the 28-year-old woman approached the crossing and "ran towards the forces while holding a knife".
"A civilian security guard who recognised what was happening called on her to stop several times," a police statement said, adding that when the woman continued to move forward "the security guard then fired several bullets".
Police distributed a photograph of the knife they said she was carrying.
Israeli-Palestinian violence flared last month in 11 days of intense fighting between Israel and Hamas in Gaza. A fragile ceasefire is largely holding, though tension remains high.
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