--- - |2 Abstract Empathy has great effect on human well‐being, promoting healthy relationships and social competence. Although it is increasingly acknowledged that infants show empathy toward others, individual differences in infants’ empathy from the first year of life have rarely been investigated longitudinally. Here we examined how negative reactivity and regulation, two temperament traits that predict empathic responses in older children and adults, relate to infants’ empathy. Infants were studied at the ages of nine (N=275) and 18 (N=301) months (194 infants were studied at both ages). Empathic responses were assessed by infants’ observed reactions to an experimenter's simulated distress. Negative reactivity (fear, sadness, and distress to limitations) and regulation (soothability and effortful control) were assessed by parental reports. Negative reactivity was also examined by infants’ observed reactions to an adult stranger (fear) and during interaction with their mothers (displays of sadness/distress). When examined cross‐sectionally, infants’ fear and distress to limitations associated with self‐distress in response to others’ distress. In contrast, when examined longitudinally, early sadness and distress to limitations, but not fear, associated with later empathic concern and inquisitiveness. Moreover, this longitudinal relation was moderated by infants’ soothability, and was evident only for children that had high soothability by the later time‐point. Our findings suggest that infants who at an earlier age show negative reactivity, react later in development with more empathy if they achieve sufficient regulation abilities. By that, the findings stress the developmental nature of temperament‐empathy relations during infancy. This article is protected by copyright. All rights reserved. - Developmental Science, Volume 0, Issue ja, -Not available-.