His comments come despite the US leader calling the wall a problem for Middle East peace.
Sharon said Israel would continue discussions with Washington over the barrier snaking through the West Bank and try to minimise its effect on Palestinians.
Bush said he and Sharon would continue to discuss the "sensitive issue".
The Israeli Prime Minister is meeting the US leader in Washington to discuss the American-backed Middle East peace plan.
The talks at the White House are expected to focus on concerns that a month-old Israeli-Palestinian ceasefire is under threat.
Palestinian information minister Nabil Amr dismissed as "entirely negative" Sharon's statement.
"He gave no single positive sign at all," Amr said.
"He is not stopping the (Jewish) settlements and he is going on with the wall."
"This means there are big obstacles in the way of the peace process and the implementation of the roadmap peace plan."
The Palestinians say an Israeli separation wall under construction in the West Bank and the continued growth of Jewish settlements are undermining Bush's own vision of an independent Palestinian state.
The Israelis counter by saying the Palestinian security forces are not using the lull in violence to prevent resistance groups re-grouping and re-arming.
Mr Bush has criticised the construction of the security wall, but he is expected to support Sharon's calls for Palestinian steps to dismantle what the Israelis describe as terrorist organisations.
Israel's decision to release 500 Palestinian prisoners is also likely to be on the agenda at the talks.
Radie Jarai, deputy minister of detainee affairs for the Palestinian Authority, said Sharon's concession to release the prisoners does not go far enough.
"The security fence will continue to be built," Sharon told a joint news conference after meeting"
Israeli prime minister
"We have about 6000 Palestinians imprisoned in Israeli jails, and to release 400, or 500, is just starting," he said.
"In the last two weeks, there were more than 300 detention cases in the West Bank and Gaza Strip. So it is just trying to mislead the public opinion that Israel is making progress in the peace process."
Muhammad Al-Hindi, of the Islamic Jihad resistance movement, told Aljazeera that Israel is putting too many conditions on prisoner releases.
He added: “If Israel does not agree with the Palestinian ministry of prisoners’ affairs on a schedule for releasing Palestinian detainees, and does not stop all attacks against the Palestinians, the truce will be halted.”