Abe's assurance in Parliament came after his announcement last week about Japan's participation in the U.S.-led TPP initiative.
Japan had resisted entering the negotiations because of concerns the TPP's free trade framework would hit Japanese farmers and Japanese agriculture industry hard through less-expensive imports.
"Farming has to be the foundation of a country," Abe said during Parliament's budget meeting and that it has defined traditional Japanese culture, Kyodo News reported. He said discarding agriculture for the sake of profit-and-loss arithmetic would cause "Japan to lose its identity."
Economic Revitalization Minister Akira Amari, appointed minister in charge of TPP issues, said the government would also protect Japan's health insurance system.
"As it is the backbone of Japan's medical system, we would work to make sure it will not be shaken," he said.
Amari said the government hasn't received written notice that Japan may not be able to renegotiate what has already been discussed by TPP members.
Besides the United States, other countries involved in the TPP negotiations on regional economic integration are: Singapore, Canada, Mexico, Australia, Brunei, Chile, Malaysia, New Zealand, Peru and Vietnam, which have a combined gross domestic product that exceeds $21 trillion.
The Office of the U.S. Trade Representative has said the participation of Canada and Mexico, the two largest trading partners of the United States, adds "significantly to the economic importance of the agreement as well as to establishing TPP as the most promising pathway to promote regional economic integration and to support the creation and retention of U.S. jobs."
Earlier reports said other countries have expressed concern over Japan's policy of seeking exemptions to tariff eliminations for items such as some farm produce. TPP calls for elimination of tariffs on all trade items.