Abstract: In this study, six different genotypes of cucumber were used as experimental materials to investigate the effects of different irrigation levels, nitrogen application rates, and temperature conditions on cucumber fruit hollow characteristics using an orthogonal experimental design.Additionally, physiologyical and biochemical indexes and microscopic were conducted and analyzed on the fruit cavities of the six genotypes, in order to provide reference for the study of cucumber fruit hollow traits and the breeding of hollow-free cucumber varieties.The results showed that among the three environmental factors, nitrogen application rate had the greatest influence on cucumber fruit hollow characteristics, followed by temperature and irrigation level.Both nitrogen application rate and temperature showed a significant positive correlation with cucumber fruit hollow grade.Furthermore, there was a significant negative correlation between chlorophyll and soluble protein content of cucumber fruit peel and hollow grade, while ABA content exhibited a significant positive correlation.However, soluble sugar and soluble solid content showed no significant correlation with hollow grade.Among these factors, chlorophyll and soluble protein content in fruit peel could be used as identification and prediction indicators for cucumber fruit hollow.Observation of paraffin sections indicated that cucumbers with larger fruit cavities may have smaller flesh cells.