We have carried out multicolor linear polarimetry (U BV RI) of the brightest stars in the area of the open cluster Trumpler 27. Our data show a high level of polarization in the stellar light with a considerable dispersion, from P = 4% to P = 9.5%. The polarization vectors of the cluster members appear to be aligned. Foreground polarization was estimated from the data of some nonmember objects, for which two different components were resolved: the first one associated with a dust cloud close to the Sun producing P<SUB>λmax</SUB> = 1.3% and θ = 146°, and a second component, the main source of polarization for the cluster members, originating in another dust cloud, which polarizes the light in the direction of θ = 29°.5. From a detailed analysis, we found that the two components have associated values E<SUB>B-V</SUB> < 0.45 for the first one and E<SUB>B-V</SUB> > 0.75 for the other. Due the difference in the orientation of both polarization vectors, almost 90° (180° at the Stokes representation), the first cloud (θ ∼ 146°) depolarizes the light strongly polarized by the second one (θ ∼ 29°.5).Facultad de Ciencias Astronómicas y Geofísicas