Loved ones of cancer patients are vulnerable, often reporting psychological distress and inadequate information provision. This research examined the use and emotional and behavioral effects of online cancer information. Compassion and fear were the strongest emotions elicited by online content, and respondents reported several cognitive, communicative, and helping behaviors. Multiple relationships between emotions and behaviors were found, including between hope and helping behaviors, anger and problem-solving, fear and seeking comfort, and sadness and a decreased likelihood of engaging in cancer prevention and detection. This study extends research on emotions and action tendencies and provides guidance for developing future online resources.