Restless legs syndrome (RLS) is common in Parkinson's disease (PD) patients and can affect the motor symptoms and non-motor symptoms (NMSs) of PD patients. This study aimed to identify the clinical factors affected by RLS in patients with PD. We included 369 de novo PD patients. RLS was assessed by face-to-face interviews and the motor symptoms and NMSs of the patients were assessed using relevant scales. RLS frequency in the patients was 12.2% (45/369). PD patients with RLS (PD-RLS) exhibited a greater global Pittsburgh Sleep Quality Index (PSQI) score than those without RLS (PD-No RLS). PD-RLS exhibited significantly greater scores in the daytime dysfunction and sleep disturbances components of the PSQI than PD-No RLS. PD-RLS exhibited a significantly greater score in the sleep/fatigue domain of the Non-Motor Symptoms Scale than PD-No RLS. The International RLS Study Group rating scale score was significantly related to PSQI components scores in the sleep disturbances, sleep latency, habitual sleep efficiency, and subjective sleep quality. RLS frequency in de novo PD patients is higher than that in the general population, and the main NMS affected by RLS in these patients is sleep disturbances. Therefore, it is necessary to manage RLS in PD patients with sleep disturbances.