This research offers a novel approach for potato wastewater (PW) bioconversion to alcohol by microwaves gelatinization, liquefaction and simultaneous saccharification and fermentation (SSF). Concentrated PW from potato processing to obtain fries was treated by gelatinization, enzymatic hydrolysis through liquefaction and saccharification, and fermentation; a mini-bioreactor was used, with low oxygen, temperature, pH and mixing control. The yeast Saccharomyces cerevisiae and a commercial mix of lactic bacteria were used for fermentations. Two fermentation systems were tested: SSF and saccharification followed by fermentation (SF). The results indicated gelatinization with microwaves at 85oC for 5 minutes as being very efficient on the starch hydrolysis, compared with the classical thermal gelatinization. SF and SSF cultivation systems showed differences in terms of RS production and consumption and ethanol production; the final values after 48 h of cultivation were around 1% RS (both SF and SSF) and 6% ethanol in SF and 7% ethanol in SSF. Yeast and lactic bacteria were not significantly influencing each other at the cultivation on PW and the lactic bacteria showed no influence on the ethanol production. The most adequate strategy was to cultivate only yeast in SSF system at 35oC for 36 hours with production of around 7% ethanol with more than 0.5 g ethanol/g RS.