PURPOSE:To obtain high fatigue strength in a connecting rod, the rod portion of which is reinforced by axially arranged unidirectional fiber molding by specifying the cross-sectional area of concentrated complex part and moldings and the total cross-sectional area of the rod portion. CONSTITUTION:A connecting rod 1 comprises a rod portion 2, and a small end portion 3 and a large end portion 4 which are solidly mounted at both end portions. The central part of the rod portion 2 is reinforced by unidirectional fiber moldings 5 axially arranged therein. In this case, the ratio Af/Ac of the cross- sectional area Af of the moldings 5 to the cross-sectional area Ac of a fiber concentrated complex part 8 of the rod portion 2 is set at 25 to 65%. The ratio Ac/A of the cross-sectional area Ac to the total cross-sectional area A of the rod portion is set at 88 to 32% if Af/Ac is 25%, and at 34 to 12% if Af/Ac is 65%. Further, the ratio Af/A is set at 8 to 22%.
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