The present study examined the psychological characteristics of surgical patients with Graves’ diseases (GD) and papillary thyroid cancer (PTC) through the 20-item Toronto Alexithymia Scale (TAS-20) and the Baum test before and after the surgery. In the pre-test [Study 1], the PTC group scored higher on “externallyoriented thinking” of the TAS-20 and drew less structured trees regarding the boundary, consistency, and inner differentiation, compared with the control group. In the post-test [Study 2], the mean score of “externally-oriented thinking” of the TAS-20 was lower, and the mean score of “difficulty identifying feelings” of the TAS-20 was higher than that of the pre-test, respectively. The trees drawn in the post-test were classified into following three clusters; “changed into a more stable structure”, “changed into a more unstable structure”, and “unchanged”. We discussed that the genuine psychotherapy is needed for those who showed more fundamental psychological changes.