: Increasing research has applied nature-based interventions to improve mental well-being and productivity in offices. However, how typical design characteristics, such as plant quantity and window view access, support attention restoration following ego-depletion in open-plan offices remains unclear. Furthermore, studies conducted in Chinese offices remain particularly scarce. This study conducted four randomised controlled experiments within a virtual open-plan office to investigate the restorative effects of indoor plant quantity and access to nature and urban window views on participants’ performance following ego-depletion. Furthermore, the effects of these interventions were compared. The four experiments included 132 (58.3% female), 126 (57.9% female), 134 (57.4% female), and 96 (52.1% female) participants, respectively. Their performances were measured using biometric sensors (physiological indices: heart rate variability (HRV) & electrodermal activity (EDA)), Psychomotor Vigilance task and Stroop tests (cognition), Positive and Negative Affect Schedule (mood), and a self-developed questionnaire (affective qualities & satisfaction). Results revealed that indoor plants (all amount levels) improved HRV and lowered EDA following ego-depletion; however, they did not affect mood and cognition. Furthermore, only a large amount enhanced affective qualities. In addition, medium and high access to nature window views reduced EDA and improved affective qualities. However, only high and medium window access increased positive and reduced negative mood, respectively. Access to urban window views improved HRV and affective qualities, while only medium access lowered EDA. Thus, plants were superior to window views in physiological and attentional restoration, whereas window views elicited higher positive affective ratings.