This study aims to construct a multidimensional instrument in assessing insight of schizophrenic patients and further to examine its relationships with other factors such as psychiatric symptoms, demographic characteristics, and course of illness. An instrument (the Schedule for assessment of Insight in Psychosis, SIP) with a 4-point rating scale was constructed to assess the insight of schizophrenic patients in five dimensions. One hundred schizophrenic patients were recruited for the study and all of them received a semi-structured interview using the SIP. Their demographic variables, length of illness and severity of psychotic symptoms were analyzed for insight. The reliability and validity of the SIP were satisfactory. Significant factors related to insight were psychotic symptoms, including both positive and negative symptoms. This study showed insight was affected by a multitude of factors, and it could be assessed quantitatively in various dimensions.