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There is not a full consensus on the functions of neural oscillations associated with nociception. The existing findings are yet to be consistent across studies. While intensity of pain has been established to be related to certain signal changes at different frequency bands, how the induction of predictable and unpredictable pain differentially alters the neural oscillations is still relatively unclear. Previous studies showed that theta, alpha, beta, and gamma band oscillations are observed in response to painful stimulation. We have investigated the neural oscillations observed between 3-30Hz in a timeframe of 1500ms after painful stimulus at the centro-parietal (Cz and CPz) and sensorimotor (C4) electrode sites. Comparing the oscillations elicited by high, medium, and low painful laser stimulation, we found that the intensity of pain differentially affected the activation in the theta, alpha, and beta frequency bands. Specifically, high-intensity painful stimulus resulted in greater power of the signals recorded at the theta band. Lower alpha band activity for high-intensity pain was only observed at C4, while the power of beta-band signals was lower for medium intensity only at the electrode sites of Cz and CPz combined. Similarly, the neural oscillations had different activation characteristics observed for predictable and unpredictable presentation of pain. When the painful stimulation was presented with a predictable cue (i.e., one cue only indicating the presented intensity), theta and beta band signals had lower amplitudes. For central cortical areas only, a lower alpha and beta band activity was observed in the trials where the painful stimuli were presented unpredictably (i.e., cues indicating two possible intensities). The present findings suggest that functional inhibition hypothesis on alpha suppression might explain the role of alpha band activity in nociception with differing intensities. The predictability effect observed for alpha band suppressions also supports the predictive coding account on nociception. The difference in theta-band activity for predictable and unpredictable pain was recorded as a novel finding in the literature, to our knowledge. Overall, bottom-up and top-down processes associated with activity differences in theta, alpha and beta-band frequencies observed for various intensities and predictability also provide us with a framework where multiple frequency bands take part in processing painful stimulation. The present study provides further insights into the effects of laser-induced pain on a neural level while emphasizing the overlaps and contradictions across previous studies and methodologies in use. The implications derived from the current study might inform future studies with a focus on pathological pain where the investigation of pain via physiological measures including neural imaging is widely used.