Mariahilf, Mountain settlement in Sankt Jakob in Defereggen, Austria.

Mariahilf is a Rotte of the Oberrotte fraction in the municipality of St. Jakob in Defereggen, lying on the valley floor of the Defereggental on the left, northern bank of the Schwarzach. To the east the Oberberg Runsen forms the boundary with the hamlet of Ranach, to the west lies the Vorderladstatt part of the Rotte Ladstatt, and on the opposite southern bank stands the village of Rinderschinken. The settlement comprises 25 house numbers, some of them semi-detached houses.

The settlement developed from a farmstead called Bruggen, which fell under the control of Bruck Castle in Lienz during the Middle Ages. The place grew into one of several hamlets scattered through the valley.

The chapel in Mariahilf, the Stöffliskapelle, is a small rectangular building without a tower, covered by a shingled gable roof and built in 1913. It is consecrated to the Passion of Christ under the title "Unser Herr im Elend". Diagonally opposite stands a wayside cross dating from the first half of the 19th century.

Mariahilf is reached via the Defereggentalstraße, which runs through the northern part of the settlement. Bus line 953 serves the stop St. Jakob i. D. Mariahilf Dorf, connecting the hamlet to public transport. The settlement lies on the left, northern bank of the Schwarzach, opposite the village of Rinderschinken.

A customs house from the 1920s was converted in 2016 into an apartment building that now offers holiday rentals to visitors. This structure recalls the settlement's location near a border and its former role in cross-border trade.