This paper examined the effect of ill health on technical efficiency of dry season vegetable farmers in Ojo Local Government Area of Lagos State, South-West, Nigeria. A total of 80 dry season vegetable farmers were sampled through a multi-stage sampling procedure. Data were analysed using descriptive statistics and stochastic frontier analysis. The results showed that majority (68%) of the farmers were within the economic active age group of 25 and 35 years. The mean number of days absent from farm work due to illness was 3 days while majority (70%) of the farmers had contact with extension workers. The major problems confronting the farmers were inadequate land, capital and pest infestation among others. The return to scale value of 1.15estimated from the Stochastic Frontier Analysis revealed that farmers were operating in stage 1 of the production surface, hence, the need to employ more resources in order to maximize benefits. The mean technical efficiency was 0.701. This implies that the efficiency of the vegetable farmers can be improved at the existing technology by about 29.9% in the short run. The health variable which was captured by illness episodes and number of days absent from work due to illness had positive coefficient and statistically significant at p < 0.10. The study therefore concludes that ill health have adverse effect on the technical efficiency of the dry season vegetable farmers in the study area, thereby reducing their productivity levels.