The article examines the issue of increased volume of military and military-technical assistance of the USSR to Afghanistan for about a year and a half - from the end of spring of 1978, when the April Revolution took place in Afghanistan, until the end of 1979 - up until the date of the entry of a limited contingent of Soviet troops into Afghanistan. Based on released top secret Soviet documents, the Soviet Union increased its military and military-technical assistance to Afghanistan becoming increasingly involved in its internal events. During the course of a year from spring 1978 until the spring of 1979 Soviet military assistance to Afghanistan increased very gradually. The number of requests by the Afghan leadership for increasing Soviet military assistance rose sharply after the Herat insurgency, which took place in March 1979. The size of Soviet military and military-technical assistance had grown significantly since the spring of 1979, also after the Herat insurgency. However as is evident from the analysis of Soviet documents, the Soviet Union chose not to resort to direct military intervention for a long time, withstanding the persistent requests of Afghan political leaders not only for providing more military assistance, but also for direct military intervention and the sending of troops. Nevertheless, the result of this ever-increasing military and military-technical assistance to Afghanistan was the Soviet military’s intervention in the civil war of a country. According to the author, Soviet involvement during the events in Afghanistan through the provision of military and military-technical assistance in ever-increasing amounts was due, not least, for the fear of losing a loyal ally on the southern borders of the USSR.