Partial-denitrification　(PD)　has　previously　been　demonstrated　to　be　another　pathway　for　nitrite　production,　which　provides　a　cost-effective　approach　for　nitrate　(NO3--N)　removal　through　combing　with　anammox.　In　this　study,　the　formation　of　PD　granules　was　firstly　investigated　in　a　sequencing　batch　reactor　(SBR)　with　influent　nitrate　of　60　mg　N/L.　The　granulation　process　was　explored　via　the　physicochemical　and　biological　characterization.　Sludge　granulation　initiated　within　the　first　20　days　with　an　average　size　of　93.7　mu　m　in　diameter,　it　experienced　a　developing,　shaping　and　matured　periods,　with　a　maximum　size　of　709.3　mu　m　obtained.　High　nitrite　production　of　PD　was　always　maintained　during　the　granulation　with　a　mean　nitrate-to-nitrite　transformation　ratio　(NTR)　of　88.3%,　and　in-situ　maximum　NO3-N　reduction　rate　of　84.9　mg　N/h/g　VSS　was　obtained.　Mature　PD　granules　hold　an　excellent　settling　property　with　5-min　sludge　volume　index　(SVI5)　of　32.0　mL/g　MLSS　obtained　and　smooth　surface　with　large　amounts　of　rod　bacteria　covered.　CaCO3　precipitates　formed　in　the　PD　process　played　a　vital　role　in　the　initial　granulation,　acting　as　the　nucleus　for　cell　attachment.　Extracellular　polymeric　substances　(EPS),　mainly　the　proteins　(PN)　content,　was　found　to　be　of　supreme　importance　in　granules　developing　and　maintaining　its　structural　stability.　Besides,　the　abundance　of　Flavobacterium　and　norank_p_-Gracilibacteria　were　revealed　to　be　in　accordance　with　the　change　of　granules　size,　seemed　to　contribute　to　sludge　granulation.　The　developed　granule-based　PD　integrated　with　anammox　process　provides　an　engineering-feasible　and　economic-favorable　solution　for　industrial　nitrate　wastewater　treatment.　(C)　2019　Elsevier　Ltd.　All　rights　reserved.