The present study investigated the effects of different types of form-focused instruction (FFI) on the acquisition of French grammatical gender attribution. A quasi-experimental study was conducted with 140 participants in six intact French as a second language (L2) classes. The classes received six 80-minute instructional sessions consisting of FFI on only sublexical cues, FFI on both sublexical cues and pronunciation, or the control condition (two classes per condition). To measure the effects of the instructional conditions, a pretest, an immediate posttest, and a delayed posttest were administered. Results showed that the participants receiving FFI on only sublexical cues showed significant improvement in binary-choice, text-completion, and listening tasks, but not in an oral picture-description task. In contrast, those receiving FFI on both sublexical cues and pronunciation showed significantly higher scores on all tasks after the instructional sessions. The present study highlights the importance of pronunciation instruction in L2 grammar acquisition and its interdependence with lexical and morphological domains.