Magnetic Fluid Hyperthermia (MFH) is an antitumoral therapy for the potential destruction of cancer cells in deep tumors. Magnetic mixed ferrites are studied materials for their possible use as biomedical devices. Manganese-gallium ferrites are currently poorly studied and one of the many proposed materials for cancer treatment by MFH, thanks to their magnetic properties, biocompatibility, and possible anti-cancer effects. The objective of this work is the evaluation of the cytotoxicity, magnetic properties, dispersion, and heating ability of Pluronic F127-coated Mn0.6Ga0.4Fe2O4 Magnetic Nanoparticles (MNPs) for their potential application on MFH. The toxicity degree of coated nanoparticles was quantified, taking amounts of 3.0, 4.5, 6.0, and 10.0 mg of MNPs per mL of aqueous suspensions and following the experimental procedure established in the Standard Test Method for Analysis of Hemolytic Properties of Nanoparticles (ASTM E2524-08). Magnetic induction technique (10.2 kA/m, 354 kHz) was used to evaluate the heating ability of coated nanoparticles and calculate their Specific Absorption Rate (SAR) values. The hemolytic assay results indicate that coated nanoparticles showed a cytotoxic percent value of less than 1.06 for all tested samples. The induction results indicate that coated nanoparticles have an improved heating ability than uncoated MNPs, reaching a 43.5 °C temperature in less time of 10 min. The estimated SAR values for tested samples were in the range of 15 to 20.7 Wg−1, which are slightly higher than uncoated particles, as an effect of a better dispersion into an aqueous medium provided by polymeric coating. The study allows concluding that a quantity of 3.0 mg/mL of Pluronic F127-coated Mn0.6Ga0.4Fe2O4 MNPs is enough to reach a localized increase of the temperature up to 43.5 °C in a time of 4 min, at the same time that avoids the damage to the red blood cells, making them an appropriated option for their potential use on MFH.