Secondary ion mass spectrometry (SIMS) is often used to determine the sulfur contents and isotope ratios of metallic alloys in meteorites or high-pressure experimental samples. However, SIMS analyses involve calibration and the determination of instrumental mass fractionation in reference materials with a matrix composition similar to that of the unknown samples. To provide metallic reference materials adapted to S measurements via SIMS, we synthesised a series of twenty-eight alloys comprising four FeNi(AESi) compositions (Fe$_{95}$Ni$_5$, Fe$_{90}$Ni$_{10}$, Fe$_{80}$Ni$_{20}$, and Fe$_{80}$Ni$_{15}$Si$_5$) with S contents varying from 100 μg g$^{-1}$ to 4 g/100g using the "melt spinning" method, which guarantees that the metal alloys are rapidly quenched at 10$^6$ K s$^{-1}$. Sulfur contents were determined at the Service d'Analyse des Roches et Minéraux at the CRPG and absolute δ$^{34}$S values were determined by multi-collector ICP-MS (MC-ICP-MS, ThermoScientific Neptune) and isotope ratio mass spectrometry (Thermoscientific Delta V). A δ$^{34}$S value of 16.01 ± 0.31‰ was consistently obtained using the MC-ICP-MS, which was indistinguishable of the δ$^{34}$S value of the FeS starting material (15.95 ± 0.08‰). It suggests that S did not undergo isotopic fractionation during the melting process. Of fifteen samples containing ≤ 5000 μg g$^{-1}$ S, SIMS measurements with 15-μm-diameter spots were repeatable to within 10% relative (1 standard deviation, 1s) for S contents and 2‰ for δ 34 S values. However, samples containing ≥ 5000 μg g$^{-1}$ S showed FeNi-FeS immiscibility, leading to minor dispersion of the S mass fractions and δ$^{34}$S values. No matrix effect was observed for Fe-Ni, Si, or S contents in terms of the calibration curves and instrumental mass fractionation. We ultimately recommend eight samples as reliable reference materials for S isotopic measurements by SIMS, which we can share worldwide with other laboratories.