The neural mechanisms underlying the online control of visuomotor tracking in humans remain poorly understood. Frontoparietal modulations in the EEG theta band [4-8 Hz] have been shown to correlate with error processing (Perfetti et al., 2011), especially in contexts of cognitive control (Pellegrino et al., 2018; van Driel et al., 2012). The objective of this study was to test the hypothesis that online control of movement is reflected in the oscillatory activity of the theta band. Electroencephalography (EEG) was recorded in 32 healthy adult participants while they performed a manual tracking task with their right hand. Two conditions were used to control the demands for error processing during movement tracking: in the first condition, the target moved along a repeating (i.e., predictable) pattern, generating low tracking errors; in the second condition, the target moved pseudo-randomly, inducing large tracking errors. Results showed that theta power was significantly different in the context of Low vs High tracking error; specifically, theta power was significantly greater in the High error context, with a peak difference occurring at electrodes overlaying the left central regions. Overall, this study extends current knowledge of the role of theta oscillations for error processing to the context of motor control. These modulations are likely to reflect cortical activity mediating the communication and integration of information within sensorimotor circuits including the motor cortex, the dorsal premotor cortex, and the parietal cortex, all of which are known to mediate online movement control (Takei et al., 2021; Archambault et al., 2015).