Momchilovtsi is an old settlement. Its historical roots are far in the past. When it was compact settled and who its founder was, for the present cannot be supported by historical documents.
The village is rich in archaeological findings clearly indicate that there are settlements from prehistoric times. Leaving visible traces are left by Thracians and Romans too. In all areas south and that near water, settlements occurred at different times.

There is a belief at the local residents that the village is settled again for the second time after the middle of 17 century. As its founders are indicated the residents of the village Raikovo now district of the town Smolyan.

The mountain with its lush and dense coniferous forests, vast pastures and cold springs, gave the reason to the first farmers to name the village with the Slavonic name of Ruenovo - coming from Rouen - and means plentiful. Later the name was changed to Upper Derekyoy.

According to the official letter of Ministry of Interior of 14th July 1924 regarding the rename of the villages with Bulgarian names, it was given a proposal to name the village Gorno Momchilovo. The Municipal Council did not approve this name and it was taken a decision to change it with Galabovo.

But on the conducted meeting after for the public consultation, the villagers disagreed.

Later on was suggested the village to be named of the legendary hero Momchil. In order to keep the literary style, the Commission added the suffix - ovtsi. This composite suffix means "ov” for possession and ''tsi" for representative of a community, which is to say that the word Momchilovtsi  as a byword noun means "followers of Momchil."

Momchilovtsi was one of the few places with Bulgarian population in the Rhodope Mountains, the Orthodox Christians who have managed to preserve Christianity, the Bulgarian language and the Rhodopean traditions.

Due to lack of enough fertile land were developed a number of crafts such as fishery, construction and homespun tailoring, which crafts the men practiced in the winter in the Mediterranean, Aegean islands and Asia Minor. In the summer they returned to their families to combine the craft with agricultural activity.
The history of the village was recreated by the late Father Konstantin Kanev in “The past of Momchilovtsi”, decorated with interesting facts, stories and tales from the past.