Background Informed consent (IC) is a fundamental element of modern clinical medicine based on the spirit of individual autonomy. Patients’ comprehension of the key elements of clinical IC is often poor. Aims and Objectives This study aimed to explore patients’ perceptions and expectations of IC process in invasive and surgical procedures. Design A cross-sectional descriptive study was carried out in Shanghai, China. Methods A self-administered structured questionnaire was developed to evaluate patients’ perceptions and expectations of the IC process. In total, 317 individuals were included in the final analysis. Results Majority (73.8%) of the process was undertaken one day prior to the procedure and nearly half (47.6%) lasted less than 15 minutes. Most (96.8%) patients were given verbal explanation information by healthcare professionals. The nature of illness, potential risks and complications (74.1%) and the necessity of the procedure (69.4%) were mostly memorized while alternative treatments rarely (13.6%). Patients expected their family members involved in the decision making and could be provided more time to read the IC document and prepare for the decision-making. What the patients got was significantly different from what they expected in the following aspects, such as who participated in IC, where and when it took place, how long it lasted and main contents that should be discussed in IC (P <0.05). Statistically significant relationship was found in expectations of IC patients and their income and payment type of medical expenses (P <0.05). Discussion This study explored patients’ expectation and perception of IC process regarding invasive procedures. Patients wanted to be more involved in IC process. To promote patient participation, more time should be given to the patients to comprehend and understand the IC document. In addition, information related with long-term issues should be discussed as a focal point. There is a need to re-consider IC process and to develop methods to promote the patients’ satisfaction in achieving autonomy.