A wafer-level packaging method of BSI image sensors includes the following steps: S1: providing a wafer package body comprising a silicon base, an interconnect layer, a hollow wall and a substrate; S2: cutting the wafer package body via a first blade in a first cutting process to separate the interconnect layer of adjacent BSI image sensors; and S3: cutting the wafer package body via a second blade in a second cutting process to obtain independent BSI image sensors. As a result, damage of the interconnect layer and the substrate may be decreased to improve performance and reliability of the BSI image sensor.