Josephus Johannes Cornelis Maria (Joop) Hox (born 1949) is a Dutch psychologist and Professor of Social Science Methodology at the Utrecht University, known for his work in the field of social research method such as survey research and multilevel modeling.

After receiving his MS in psychology, he received his PhD in 1986 from the University of Amsterdam under supervision of Don Mellenbergh with a thesis, entitled "Het gebruik van hulptheorieën bij operationalisering: een studie rond het begrip subjectief welbevinden" (The use of auxiliary theories on operationalization: a study of the concept of subjective well-being).

From 1977 to 1996 Hox was assistant professor at the University of Amsterdam at the department of Gerard de Zeeuw.

In 1997 he was appointed Professor of Social Science Methodology at the Faculty of Social Sciences of the Utrecht University, which he started with the inaugural lecture, entitled "nieuws onder de zon: nieuwe oplossingen voor oude problemen" (There is nothing new under the sun: new solutions to old problems).

Hox also participates in the Interuniversity Graduate School of Psychometrics and Socio Metrics (IOPS) and chaired the Netherlands Organization for Social-Methodological Research (NOSMO).