From a previous analysis of the proposed gyroscope test of the Lense-Thirring effect, it is known that all perturbations that contribute more than ${10}^{-3\mathrm{}}$ sec/yr to the precession of the gyroscope must be taken into account. A frame of reference is obtained by rigidly attaching the gyro housing to a telescope which is trained on some reference star. Here we point out that the deflection of the light from the reference star due to the sun's gravitational field can give rise to an apparent precession of the gyroscope equal to ($4.1\times {10}^{-3\mathrm{}} cot\frac{1}{2}\theta$) sec, where $\theta$ is the angle between the earth-sun direction and the earth-star direction ($\pi \ge \theta >0\mathrm{}$). Thus, over a six-month period, this could amount to as much as 1.75 sec, depending on the angle which the sun-star line makes with the ecliptic.

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