This study investigated the associations among negative mood regulation expectancies (NMRE), attitude toward psychotherapy, comfortableness with expressing positive and negative affect, and suicidal ideation. Participants were 68 female and 2 male freshman students attending a school training them to become nursery school teachers in Japan. Correlational analyses showed that participants with higher NMRE had a more positive attitude toward seeking professional psychological help, felt more comfortable expressing their positive and negative feelings, especially positive, and were less likely to have suicidal wishes and plans. Also, individuals who scored high on attitude toward seeking help tended to feel comfortable expressing their positive and negative affect. In simultaneous multiple regression analyses, high NMRE uniquely predicted a lower suicidal ideation, independent of attitude toward seeking help and comfortableness with expressing feelings. Results support the reliability and validity of the Japanese NMR scale.