Assortative mating for age and several anthropometric characteristics is considered in a sample of 68–70 husband-wife pairs from a rural Zapotec-speaking community in the Valley of Oaxaca in southern Mexico. Conditions in the community with a population of approximately 1700 indicate chronic, mild-to-moderate undernutrition as reflected in high infant mortality rates, smaller body size of school children, and delayed biological maturation. Phenotypic assortative mating, as expressed in husband-wife correlations, is significant for age (r = 0·96), stature (r = 0·35) and grip strength (r = 0·29), but is not significant for body weight (r = 0·01), arm circumference (r = 0·07), the estimated midarm muscle circumference (r = 0·003), Quetelet's index (r = 0·02), and the ponderal index (r = 0·11). Controlling for age of husband and wife reduces the correlations for stature (r = 0·24) and grip strength (r = 0·12), but increases those for arm circumference (r = 0·21) and estimated midarm muscle circumference (r = 0·16). Grouping the spouses into younger (under 30 years of age) and older (30 years and older) results in significant spouse correlations for age, stature, arm circumference and estimated midarm muscle circumference in the younger group and for only age and fatness in the older group.