This study identifies the prevalence of suicidal ideation and its relationship with post- traumatic stress disorder (PTSD) in people affected by the earthquake and tsunami that occurred in Chile on February 27th 2010. Davidson Trauma Scale and an item from SPRINT -E that measures suicidal ideation were applied to 247 participants. An 8.9% prevalence of suicidal ideation was found, while 4,9% presents suicidal ideation and PTSD with an important pattern of association (rtc = 4.4; CC = .267) and a significant correlation between these factors (r= ,277; p < ,01). In addition, performing as a housewife, having a family member affected by the disaster, and have PTSD are major risk factors for suicidal ideation. It is recommended that the health network begin considering these factors when assessing and intervening populations affected by disasters.Este estudio identifica la prevalencia de ideación suicida y su relación con el trastorno de estrés postraumático (TEPT) en personas afectadas por el terremoto y tsunami del 27 de febrero de 2010 en Chile. Se aplicó a 247 participantes la Escala de Trauma de Davidson y un ítem del instrumento SPRINT-E que mide ideación suicida. Se encontró un 8,9% de prevalencia de ideación suicida, mientras que el 4,9% presenta ideación suicida y TEPT con una pauta de asociación importante (rtc = 4,4; CC = ,267). Además, desempeñarse como ama de casa, tener un familiar afectado por el desastre, y tener TEPT son los principales factores de riesgo para la ideación suicida. Se recomienda a la red de salud tenerlos presentes a la hora de evaluar e intervenir poblaciones afectadas por desastres.