Near-infrared observations of 82 stars in h and χ Persei (NGC 869 and 884) were obtained with the Mexican National Observatory infrared photometer/spectrometer on the 2.1 m telescope at San Pedro Mártir, Baja California. The JHK photometry covers most of the stars in the upper main sequence of the central parts of the clusters as well as the giants and supergiants in a more extended region, with additional L' and M measurements of the brightest members. In Figure 1 the (J-H) vs (H-K) and (H-K) vs (K-L) diagrams are presented. In order to complement the available good quality UBV photometry, we carried out photoelectric measurements of 23 stars in our sample for which only low quality photographic data has been published. These observations were made with the pulse-counting photometer attached to the newly refurbished 1.5 m telescope at San Pedro Mártir.