We present ISOPHOT spectrophotometric observations of SS 433 at four different orbital phases in 1996 and 1997 .
The He I + He II lines in both spectra of SS 433 and the Wolf-Rayet star WR 147 , a WN8+BO5 binary system , closely match .
The 2.5 – 12 \mu m continuum radiation is due to an expanding wind free-free emission in an intermediate case between optically thick and optically thin regime .
A rough mass loss rate evaluation gives about \sim 1.4 \times 10 ^ { -4 } \mathrm { M } _ { \odot } . \mathrm { yr } ^ { -1 } .
Results are consistent with a Wolf-Rayet-like companion to the compact object in SS 433 .