. The Perceived Stress Scale (PSS) is the most well-known self-report measure to assess perceived psychological stress.. The objective of the study was to analyze the psychometric properties of three versions of the Perceived Stress Scale (PSS-4, PSS-10 and PSS-14) in Ecuador.. A sample of 7905 university students (46% men and 54% women) from Ecuador were surveyed using all three versions of PSS.. All three versions showed a satisfactory adjustment with a bifactorial structure based on the item structure rather than underlying dimensions of psychological stress. The reliability was also adequate, with Alpha and Omega coefficients [α = 0.85 and ω = 0.80 for PSS-14; α = 0.85 and ω = 0.87 for PSS-10; α = 0.74 and ω = 0.78 for PSS-4] respectively. Psychological stress scores positively correlated with multiple health indicators such as loneliness, psychological inflexibility, alcohol consumption, and presence of anxiety and depression symptoms, and negatively with resilience.. The use of PSS-10 based on its best goodness of fit and PSS-4 as the shortest version are recommended to measure psychological stress, rather than the original PSS-14 version. Psychological stress was significantly higher in women than men.