The key Tokyo Commodity Exchange rubber contract for August delivery settled down 8.1 yen, or 2.4 percent, at 324.5 yen. The contract fell as low as 320.4 yen, the lowest since Feb. 20.
The contract, however, remains in sight of 5-month high at 344.4 yen struck in late February.
The most active Shanghai rubber contract for May delivery fell to 28,085 yuan per tonne from 28,530 yuan on Tuesday.
The front-month April rubber contract on the SICOM in Singapore was last traded at 378.40 US cents per kg, up 1.7 cents.
Bridgestone Corp, the world's biggest tyre maker, said on Wednesday solid demand for replacement tyres in Asia would help boost its global tyre production by 5.3 percent to 1.99 million tonnes in 2012.
Japan's Nikkei average fell for the third session on Wednesday as fears that Greece may not meet its bond swap deadline sapped risk appetite, while Brazil's weaker annual growth added to fears of a slowdown in the global economy.