The A-phase of MnSi exhibits a topological Hall effect (THE) that confirms the presence of a skyrmion lattice, as inferred from small-angle neutron scattering (SANS) data. The SANS data suggest a triple-Q spin structure, which is interpreted as a lattice of skyrmions—topologically stable spin configurations. The THE, observed in the A-phase, is distinct from the normal Hall effect and the anomalous Hall effect (AHE), and is attributed to a topologically quantized Berry phase. This Berry phase arises from the movement of conduction electrons through the spin structure, accumulating a phase that reflects the chirality and winding number of the skyrmions. The Hall effect measurements in MnSi reveal a significant anomalous contribution in the A-phase, with a sign opposite to the normal Hall effect and a magnitude consistent with the skyrmion density derived from SANS and theoretical models. This observation provides direct evidence that the spin structure seen in neutron scattering corresponds to a skyrmion lattice. The THE is a direct manifestation of the topological properties of the spin structure, confirming the existence of topologically stable knots in the spin configuration. The A-phase of MnSi is characterized by a first-order phase transition, distinct from the conical phase. The spin structure in the A-phase is found to be perpendicular to the applied magnetic field, a feature that is consistent with the skyrmion lattice model. The Hall resistivity measurements, conducted in a six-terminal configuration, show a clear additional contribution in the A-phase, which is attributed to the topological nature of the spin structure. Theoretical analysis suggests that the effective magnetic field generated by the skyrmion lattice is quantized and oriented opposite to the applied field. The calculated effective field, combined with the measured polarization, leads to a theoretical prediction of the Hall effect that is in remarkable agreement with experimental results. The study confirms the existence of a skyrmion lattice in the A-phase of MnSi, as evidenced by the topological Hall effect. This work provides a direct observation of a topologically quantized Berry phase, unambiguously identifying the spin structure inferred from neutron scattering.The A-phase of MnSi exhibits a topological Hall effect (THE) that confirms the presence of a skyrmion lattice, as inferred from small-angle neutron scattering (SANS) data. The SANS data suggest a triple-Q spin structure, which is interpreted as a lattice of skyrmions—topologically stable spin configurations. The THE, observed in the A-phase, is distinct from the normal Hall effect and the anomalous Hall effect (AHE), and is attributed to a topologically quantized Berry phase. This Berry phase arises from the movement of conduction electrons through the spin structure, accumulating a phase that reflects the chirality and winding number of the skyrmions. The Hall effect measurements in MnSi reveal a significant anomalous contribution in the A-phase, with a sign opposite to the normal Hall effect and a magnitude consistent with the skyrmion density derived from SANS and theoretical models. This observation provides direct evidence that the spin structure seen in neutron scattering corresponds to a skyrmion lattice. The THE is a direct manifestation of the topological properties of the spin structure, confirming the existence of topologically stable knots in the spin configuration. The A-phase of MnSi is characterized by a first-order phase transition, distinct from the conical phase. The spin structure in the A-phase is found to be perpendicular to the applied magnetic field, a feature that is consistent with the skyrmion lattice model. The Hall resistivity measurements, conducted in a six-terminal configuration, show a clear additional contribution in the A-phase, which is attributed to the topological nature of the spin structure. Theoretical analysis suggests that the effective magnetic field generated by the skyrmion lattice is quantized and oriented opposite to the applied field. The calculated effective field, combined with the measured polarization, leads to a theoretical prediction of the Hall effect that is in remarkable agreement with experimental results. The study confirms the existence of a skyrmion lattice in the A-phase of MnSi, as evidenced by the topological Hall effect. This work provides a direct observation of a topologically quantized Berry phase, unambiguously identifying the spin structure inferred from neutron scattering.