Microscale single-crystal silicon (SCS) fatigue test structures having a notch at the midsection were subjected to a localized laser treatment with a 1 J/cm2 laser energy for 5 pulses while tilted by 45°. As-fabricated and laser-treated samples oriented along the <110> direction were subjected to fatigue test using the same loading (1.7° rotation angle) and environmental (25 ℃ and 50% relative humidity) conditions to study the effect of laser treatment on fatigue performance. As-fabricated samples showed an average fatigue life of 5.6 × 108 cycles with the data being scattered within an order of magnitude. On the other hand, laser-treated samples showed a significant variation in fatigue life. Two samples showed an improved fatigue performance, one sample showed a comparable performance to as-fabricated samples, and two samples fractured instantly as the fatigue test started. Samples that fractured instantly showed the development of protrusions at the notch tip after laser treatment. These protrusions might have caused stress concentration that led to premature failure. Protrusions might indicate fluctuations in laser energy, which could be due to sample misplacement; hence, a more precise control of sample placement is needed for a consistent improvement in fatigue life after laser treatment.