Well-being has been measured based on different perspectives in positive psychology. However, it is necessary to measure affects and emotions correctly and to explore the independence of positive and negative affect. This cross-sectional study adapts and validates the Scale of Positive and Negative Experience (SPANE) with a non-probabilistic sample of 821 Spanish adults. A confirmatory factor analysis confirmed two related factors with two correlated errors. The average variance extracted was 0.502 for negative affect (SPANE-N) and 0.588 for positive affect (SPANE-P). The composite reliability was 0.791 for SPANE-N and 0.858 for SPANE-P. Measurement invariance analysis showed evidence of scalar invariance. Item-total corrected polyserial correlations showed values between 0.47 and 0.76. The path analysis used to test temporal stability, and the structural equation models used to test convergent and concurrent validity with other well-being measures, showed good fit. All path coefficients were statistically significant and over 0.480. For the validity models, the magnitude of the correlations was large and in the expected direction. The Spanish version of the SPANE show good psychometric properties. Future studies of emotional well-being in Spain can benefit from the use of this scale, and new studies must test cross-cultural invariance