The impact of light absorbing particles (LAPs), i.e. black carbon (BC) and dust, in the cryosphere, is receiving increasing attention in the scientific community, because they may be contributing to the accelerating retreat of glaciers. The Huaytapallana mountain range in the central region of Peru is vulnerable to this effect; it has been estimated that its glacier surface has decreased by 56% in the last 27 years. In this study, we present first measurements of LAPs, in terms of effective black carbon (eBC), in the surface snow (0-2 cm deep) in the Huaytapallana glacier between November 2015 and October 2016. The eBC mass was obtained using the new thermo-optical Light Absorption Heating Method (LAHM). The average of eBC in the surface layer was 31.1 ± 22.2 ppb. Applying the Snow, Ice, and Aerosol Radiation (SNICAR) model we estimated a reduction in albedo from the eBC ranging from 0.6 to 5.0%. The radiative forcing (RF) of the eBC was calculated, to be on average 11.8±7.8 W m -2 . During winter and spring seasons, it further increased by 157% and 134%, respectively, relative to the mean. Therefore, the impact of the eBC is an important factor in the retreat of the glacier Huaytapallana and must be considered in the hydrological prediction models of water availability.