The purpose of this work was to evaluate the efficacy of the microalgae Spirulina platensis in the bioremediation of leachate from the solid waste treatment plant of San Jerónimo de Tunán, Junín, Peru. Initially, a pilot test was carried out using undiluted leachate (100%) in which no microalgal growth was evidenced, in response to this, a second experimental phase was designed using a 40% dilution with distilled water complemented with essential mineral salts to optimize the culture medium. Treatments were established with different volumes of microalgae: N-01 and N-02 with 550 mL, and M-01 and M-02 with 750 mL. The experimental tests were carried out over seven days for N-01 and M-01, and fourteen days for N-02 and M-02. During the experimental period, physicochemical parameters (pH, temperature, electrical conductivity, turbidity, BOD and COD) were monitored, as well as the removal capacity of heavy metals (lead, zinc, iron, chromium, arsenic and cadmium). The results showed a decrease in turbidity, with final values of 42.56 and 35.90 NTU in the one-week treatments (N-01 and M-01) and in the two-week treatments (N-02 and M-02) values of 45.30 and 49.43 NTU were recorded respectively. BOD and COD values, especially in longer duration treatments, BOD was reduced between 15.98% and 19.86% in one week, reaching up to 34.31% and 37.09% in two weeks. On the other hand, COD was reduced by 24.57% and 26.62% in one week, and up to 42.08% and 45.23% in two weeks. Regarding heavy metals, variable removals were obtained: lead (69.33-80.67%), zinc (44.34-50.91%), iron (70.73-75.72%), chromium (64.73-75.84%), arsenic (61.49-64.87%) and cadmium (55.55-73.33%). The findings support the potential of Spirulina platensis as an effective and promising alternative for leachate bioremediation.