OBJECTIVES: Most patients with myocardial infarction in Colombia are treated with streptokynase, despite tenecteplase being recognized as more effective. Our objective was to evaluate the cost-effectiveness and cost-utility of tenecteplase, compared with streptokinase, in the treatment of ST elevation myocardial infarction. METHODS: We designed a decision tree model, from the perspective of the Colombian health system. We calculated quality adjusted life years (QALY) gained (using data Tuft's registry), as well as cost per death, and cost per major outcome averted (death, stroke, severe heart failure). The costs were estimated in Colombian pesos for 2012 (Exchange rate 1US$ = COP$1785) using national tariff manuals (Social Security 2001 with inflation adjustment) and resource use obtained from our local university hospital, validated by national expert panel. We performed a probabilistic and deterministic sensitivity analysis. RESULTS: The average total cost for a tenecteplase treated patient was US$1456. The cost per incremental QALY gained with tenecteplase was US$14,447; US$95,302 per death averted, and US$38,578 for major outcome averted. The average total cost for the treatment of acute phase of all myocardial infarctions for 2012 was estimated in US$728,000. Monte Carlo simulation acceptability curve showed that in 85% of the trials the result would be cost-effective, assuming a willingness to pay of up to three times the per capita gross domestic product (Colombia's per capita GDP is US$6723). If the cost of tenecteplase were lowered from US$2066 to US$389 the cost per QALY would reach the one per capita GDP threshold. CONCLUSIONS: Our results suggest that tenecteplase is cost effective if we accept the three-times per capita GDP threshold.