Background Cognitive remediation therapy (CRT) has proven to be effective in treating cognitive deficits in schizophrenia. The current study aimed to assess the efficacy of CRT on psychotic symptoms and cognitive complaints. Methods We contrasted the changes in symptoms and cognitive complaints in patients with schizophrenia and related disorders who received 2 novel CRTs, one targeting mental state attribution, and the other, mental flexibility, compared with a control group given treatment as usual. Twenty-four patients with schizophrenia and related disorders were pseudo-randomly assigned to 1 of 3 groups. Psychotic symptoms and subjective complaints about their cognitive deficits were evaluated twice in each group, before and after therapy. Scores obtained pre- and post-therapy were compared between the groups. Results The therapies were well-tolerated by the participants, and no one dropped out of the study. Symptoms decreased after therapy, but not in the control group. The mental flexibility group showed the most improvement. Moreover, patients in this group described a subjective diminution of their cognitive deficits. Conclusions Our results demonstrate that CRT can be useful to reduce clinical symptoms while they suggest an impact of CRT on cognitive complaints in patients with schizophrenia.