This study aimed to investigate the immediate effects of the secretory immunoglobulin A (sIgA), α-amylase activity and blood pressure levels after the application of a Reiki session in nurses with Burnout Syndrome. A randomized, double-blind, placebo-controlled, crossover design was conducted to compare the immediate effects of Reiki versus control intervention (Hand-off sham intervention) in nurses with Burnout Syndrome. Sample was composed of eighteen nurses (aged 34-56 years) with burnout syndrome. Participants were randomly assigned to receive either a Reiki treatment or a placebo (sham Reiki) treatment, according to the established order in two different days. The ANOVA showed a significant interaction time x intervention for diastolic blood pressure (F=4.92, P=0.04) and sIgA concentration (F=4.71, P=0.04). A Reiki session can produce an immediate and statistically significant improvement in sIgA concentration and diastolic blood pressure in nurses with Burnout Syndrome.