The 86-year-old leader repeated threats to nationalize foreign firms, threatening to retaliate against firms such as Rio Tinto and Anglo American, which operate in Zimbabwe.
"We ask them, think again, think now. Is it sanctions or no sanctions. We will be very, very strict to the extent of refusing investment from those countries (that have imposed sanctions)," Mugabe told ZANU-PF supporters at the end of the party's annual conference.
"If you have companies here, organizations here, we will work against them also."
He told reporters after the conference that the companies "have to get their mother countries to remove sanctions or there will be sanctions against them."
Anglo American and Rio Tinto together with financial services firms Barclays Plc and Standard Chartered and food group Nestle are some of the large foreign-owned companies with investments in Zimbabwe.
The government early this year published rules forcing foreign-owned companies worth over $500,000 to sell at least 51 percent of their shares to local blacks.
"Why should Anglo American continue to take our gold out? Why should Rio Tinto continue to take our gold out? If the sanctions remain and continue, those processes will have to stop," Mugabe said.
"Don't expect your banks here will remain what they are. We are not fools."
Anglo American has in the past ten years sold its mines and sugar estates in Zimbabwe but Anglo Platinum is developing a platinum mine in central Zimbabwe while Rio Tinto owns a diamond mine in the southwest of the country.
Analysts say the empowerment rules have created uncertainty and deterred the billions of dollars of foreign investment required to rebuild the economy after a decade of mismanagement under Mugabe's ZANU-PF administration.
The veteran leader says the country has suffered from sanctions imposed by the European Union, United States and Australia and says this is punishment for seizing white-owned farms for landless blacks.
Mugabe said his party was well prepared for elections next year, adding his opponents would not win as happened in 2008 when ZANU-PF lost its majority in parliament.
Mugabe also lost the presidential vote to Movement for Democratic Change leader Morgan Tsvangirai but retained power after a disputed run-off vote, which forced the two rivals to form a power-sharing government last year.
"What happened in 2008 is gone. The year 2008 is not coming back, never ever, never ever. ZANU-PF operates as an entity with a mission and we are on a mission to re-establish ourselves, our dominance," he told his supporters.
When asked by reporters whether he was confident of victory, he said: "Sure, why not."
ZANU-PF, which officially endorsed Mugabe as presidential candidate, also resolved to expel envoys and relief agencies who meddle in local politics, tasked the government to draft a treason law for people or organizations that call for sanctions and to hold elections next year.
