We assessed both current maladaptive personality traits (MPTs) and, retrospectively, premorbid MPTs in patients with schizophrenia spectrum disorders (SSDs). This was to examine whether the patients had the impression that their personality had changed and which traits were affected. We also wanted to determine whether the perceived changes could be explained by SSD psychopathology. MPTs were assessed using the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, diagnoses, axis II disorders, screening questionnaire and interview, integrating questions on subjective estimation of premorbid MPTs in moderately ill SSD patients. Forty-five patients were included. Premorbid MPTs were remembered as significantly less pronounced than current MPTs for the whole spectrum of personality traits (p < 0.001). Antisocial traits had worsened significantly less (p < 0.001), and borderline and obsessive-compulsive traits had worsened significantly more (both p < 0.01) than the mean increase. Associations between MPT increase and SSD psychopathology were significant for schizotypal, avoidant, and depressive traits. According to the patients' retrospective assessment, MPTs increased through onset and course of SSDs. Memory bias, depressed mood, and SSD symptoms alone could not sufficiently explain these differences. Subjective MPT increase may play a role for the patients' concept of illness, quality of life, and adherence to therapeutic interventions. It should be addressed in SSD treatment.