Abstract: Accurate and efficient interpretation of fracture parameters using optical fiber strain measurements at the fracture front is crucial for the broad application of optical fiber strain technology in adjacent wells. For this purpose, a method for calculating optical fiber strain was established based on three-dimensional displacement discontinuous boundary elements, and a fracture parameter inversion model based on optical fiber strain at the front margin of fracture was built. Further, based on the optical fiber strain model, calculation and analysis were performed for the variation characteristics of the distribution of optical fiber strain at the front margin of fracture with fracture parameters, and the relational expressions between the peak strain and zero strain positions and the fracture parameters were established. Next, the feasibility of inverting fracture parameters by optical fiber strain at the front margin of fracture was demonstrated using the forward modeling results of optical fiber strain as the artificially synthesized monitoring data, Finally, using the optical fiber strain monitoring results from the North American hydraulic fracturing test site, the actual well fracture parameters were interpreted based on optical fiber strain at the front margin of fracture. The research shows as follows: (1)The optical fiber strain at the front margin of fracture is related to the distribution of fracture length, height, and width, and is most sensitive to fracture length. (2)The zero strain position is sensitive to fracture height, while the peak strain position is not sensitive to fracture height. The fracture length can be interpreted quickly by the peak strain position. (3)The interior point method can effectively solve the inversion problem, characterized with high computational efficiency, and is suitable for engineering application. (4)The optical fiber strain in adjacent wells based on the front margin of fracture can effectively interpret the variation of fracture length, while the distribution of fracture height, fracture width, and fracture width has high multiplicity of solutions.