The research developed in this paper is based on micro data available in Programme for the International Assessment of Adult Competencies (PIAAC). The research aimed to estimate the size of both forms of labour market mismatch: education mismatch and skill mismatch. The first measure of job mismatch is based on workers’ self-assessment. The second one uses the PIAAC assessment regarding the proficiency for each skill dimension (literacy, numeracy and problem solving in technology rich environments). The labor market mismatch was measured for Spain and Italy datasets for the higher education graduates whose occupations are included in Major Group two Professionals, according to the International Standard Classification of Occupations. The estimation results showed that the two measures of labour market mismatch are not correlated.