The goal of this study was to examine the effect of excessive crying in early infancy on the development of emotion self-regulation. Cry diaries were used to categorize excessive criers and typical criers at 6 weeks of age. At 5 and 10 months of age, infants and mothers participated in procedures to elicit infant reactivity and regulation during a frustration task and maternal sensitivity and intrusiveness during a free-play session. Last, maternal ratings of temperament were obtained. Results revealed excessive criers to show higher levels of negative reactivity than typical criers. Excessive criers also demonstrated lower regulation, but this finding was only significant for male infants. Boys in the excessive criers group exhibited the lowest level of emotion self-regulation. Maternal behavior and ratings of temperament at 5 and 10 months failed to distinguish the 2 cry groups. The findings suggest that excessive crying may influence the developmental trajectory of the ability of boys to self-regulate emotion. The hypothesized processes involved in this outcome are discussed.