Boys with hard lumps in their breasts will not affect their height development if they are caused by physiological factors, but if they are caused by pathological factors, they may affect their height development. 1. Physiological factors: in the process of development, due to the influence of hormonal stimulation during puberty, there may be hard lumps in the chest, with the end of puberty, these hard lumps will gradually disappear after the hormone levels return to normal, no need to worry about it, it will not have an impact on the development of height, pay attention to the usual appropriate exercise, dietary control, and adjust the mentality. 2. Pathological factors: If the hard lumps are painful and serious, and the growth rate is faster, it is considered to be related to breast hyperplasia or breast tumors and other diseases, which have a certain effect on the growth hormone and may affect the development of height, so it needs to be treated in time to avoid delaying the best time. When parents find boys with hard lumps in the breast, it is recommended that they take their children to the hospital for relevant examinations in a timely manner to clarify the cause of the disease and provide timely treatment, in order to prevent the impact on the growth and development of the organism.