Alexander F. Schier (born 1964) is a Professor of Cell Biology and the Director of the Biozentrum University of Basel, Switzerland.

He conducted his postdoctoral research in Wolfgang Driever's lab at the Massachusetts General Hospital and Harvard University in Boston, US.

In 1996, Schier was recruited as assistant professor in the Developmental Genetics Program to the Skirball Institute and Department of Cell Biology, NYU School of Medicine.

Schier is internationally recognized for his pioneering work on vertebrate development using zebrafish (Danio rerio) as a model organism.

He has contributed to the development of zebrafish as model system, including positional cloning,[6] germ-line replacement to generate maternal-effect mutants,[24] photobleaching and photo conversion,[11] Brainbow imaging,[15] brain activity atlas,[25] small molecule profiling,[22] transcriptomics[20][26] and epigenomics,[19] gene annotation,[12][20][27][28] CRISPR/Cas9 genome editing,[29][30][31] lineage tracing by genomic barcode editing[32] and reconstruction of developmental trajectories by single-cell RNA-sequencing.