Background: Pain may be reported in one-half to three-fourths of children with cancer and other terminal conditions and anxiety in about one-third of them. Pharmacologic methods do not always give satisfactory symptom relief. Complementary therapies such as Reiki may help children manage symptoms. Objective: This pre-post mixed-methods single group pilot study examined feasibility, acceptability, and the outcomes of pain, anxiety, and relaxation using Reiki therapy with children receiving palliative care. Methods: A convenience sample of children ages 7 to 16 and their parents were recruited from a palliative care service. Two 24-minute Reiki sessions were completed at the children's home. Paired t tests or Wilcoxon signed-rank tests were calculated to compare change from pre to post for outcome variables. Significance was set at P < .10. Cohen d effect sizes were calculated. Results: The final sample included 8 verbal and 8 nonverbal children, 16 mothers, and 1 nurse. All mean scores for outcome variables decreased from pre- to posttreatment for both sessions. Significant decreases for pain for treatment 1 in nonverbal children (P = .063) and for respiratory rate for treatment 2 in verbal children (P = .009). Cohen d effect sizes were medium to large for most outcome measures. Discussion: Decreased mean scores for outcome measures indicate that Reiki therapy did decrease pain, anxiety, heart, and respiratory rates, but small sample size deterred statistical significance. This preliminary work suggests that complementary methods of treatment such as Reiki may be beneficial to support traditional methods to manage pain and anxiety in children receiving palliative care.