Objective:To observe the clinical phenotype of patients with CACNA1F gene variant. Methods:A retrospective clinical study. From January 1, 2022 to October 1, 2023, 36 patients with CACNA1F gene mutation-related eye diseases diagnosed by clinical examination and genetic testing in Changsha Aier Eye Hospital and Jinan Purui Eye Hospital were included in the study. All patients underwent best-corrected visual acuity (BCVA), medical optometry, fundus color photography, optical coherence tomography, full-field electroretinography (ERG), nystagmus examination, and genetic whole-exon sequencing. BCVA was performed using log visual acuity charts and converted to (logMAR). The nystagmus examination was performed using a helmet-mounted multifunctional video eye movement recording system. The clinical phenotypic characteristics were observed. Results:At total of 36 patients were male, aged was (6.69±5.26) years. There were 36 cases of myopia (38.89%, 14/36), and the spherical equivalent was (?3.01±4.84) D. There were 14 different genetic variants including 7 cases of pathogenic variants, 20 cases of suspected pathogenic variants and 9 cases of unknown pathogenic variants, respectively. logMAR BCVA was 0.67±0.27; 26 patients had optic nerve atrophy (72.22%, 26/36); 6 had optical nerve hypoplasia (16.67%, 6/36). Fundus pigment dysplasia with mild iris transillumination was found in 4 cases (11.11%, 4/36). There were 5 cases of foveal dysplasia (Thomas grade) 1 (13.89%, 5/36). In full-field ERG examination, the B-wave reduction of the maximum mixed reaction of dark adaptation showed a negative waveform, and the amplitude of the shock potential was seriously reduced. The main phenotypes were residual type (residual dark adaptation 0.01 reaction wave and bright adaptation 3.0 reaction wave, and the response decreased at 30 Hz to a double-peak wide wave), dominant type of bright adaptation decreased (all light adaptation extinguished, all dark adaptation extinguished), and total extinction type (all light adaptation extinguished). Among them, 10 cases presented with residual ERG (27.78%, 10/36), 8 cases with photopic reduced ERG (22.22%, 8/36) and 18 with extinguished ERG (50.00%, 18/36). Low amplitude and high frequency pendulum (PLAHF) nystagmus waverforms were found in 32 cases (88.89%, 32/36), head oscillation in 27 cases (75.00%, 27/36) and chin up abnormal head posture in 26 cases (72.22%, 26/36), respectively.Conclusions:CACNA1F Gene variant eye diseases had diverse clinical phenotype. Clinical phenotype of PLAHF nystagmus is closely related with CACNA1F gene variant eye disease.