Secretory immunoglobulin A (sIgA) in saliva and cardiovascular reactions to mental arithmetic and cold pressor tasks were recorded in 16 healthy young men on two sessions, 4 weeks apart. Both tasks elicited significant increases in sIgA secretion rate, reflecting increases in both salivary volume and sIgA concentration. Whereas mental arithmetic elicited a mixed pattern of alpha- and beta-adrenergic cardiovascular reactions, the pattern of reactions to cold pressor was predominantly alpha-adrenergic. Task levels of sIgA secretion rate, sIgA concentration, and saliva volume showed moderate to high test–retest reliability (r= .52–.83), although test-retest correlations were less impressive for change scores (r=−.19–.53). The pattern of correlations between change in sIgA secretion rate and cardiovascular reactivity variables was inconsistent.