Objective To compare the characteristics of tremor and non-motor symptoms in patients with essential tremor (ET) and patients with Parkinson's disease developed from essential tremor (ET-PD). Methods From March, 2016 to August, 2017, 30 ET patients and 17 ET-PD patients were investigated with the general questionnaire, Hamilton Depression Scale (HAMD), Hamilton Anxiety Scale (HAMA), Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA), and were measured with transcranial sonography and the frequency, amplitude and contraction patterns of resting and postural tremors. Results Compared with the ET patients, there were more patients reported olfactory dysfunction and rapid eye movement behavior disorder (RBD) in ET-PD patients (χ2>4.656, P<0.05). Meanwhile, the area of hyperechogenicity in substantia nigra was greater (t=2.164, P<0.05), the incidence of lower limb tremor and mandibular tremor was more (χ2>8.745, P<0.01), the frequency of rest and postural tremor in the head and upper limbs was less (t>2.082, P<0.05). The rest and postural tremors in the upper limbs were mainly synchronous in ET patients, whereas it was alternating in ET-PD patients (χ2>3.943, P<0.05). Conclusion Some differences of non-motor symptoms and tremor are found in patients with ET-PD and ET. When ET patients suffer from hyposmia, RBD, or the site, frequency and contraction patterns of tremor changes, they may develop to PD.