To　further　explore　the　safety　assurance　technology　for　reclaimed　water,　a　pilot　ozone　oxidation-biological　activated　coke　filtration　system　(O3-BACK)　was　built　and　its　effects　on　the　removal　of　organic　pollutants　and　pathogenic　bacteria　from　secondary　effluents　of　municipal　wastewater　treatment　plants,　as　well　as　on　the　comprehensive　biotoxicity　of　luminescent　bacteria　were　investigated.　Results　showed　that　the　development　of　activated　coke　filtration　column　from　adsorption　saturation　to　biological　activated　coke　could　be　divided　into　three　stages.　With　the　introduction　of　O3　pretreatment　unit,　the　average　removal　amount　and　removal　rate　of　CODCr　by　subsequent　BACK　columns　in　the　stabilization　period　increased　by　20.81%　and　28.35%　respectively,　compared　with　BACK　filtration　alone.　The　effluent　CODCr,　UV254,　chromaticity,　and　turbidity　of　BACK　column　maintained　at　12.74　mg/L,　0.04　cm-1,　2　degree,　and　0.75　NTU.　O3　oxidation　was　effective　in　the　removal　of　humic　substances,　aromatic　protein　fluorescent　fractions,　and　trace　organic　pollutants.　Except　for　perfluorooctanoic　acid,　the　concentrations　of　11　trace　organics　such　as　sulfamethoxazole　in　BACK　effluent　were　reduced　to　less　than　10　ng/L.　O3　inactivated　fecal　coliform　(FC)　by　nearly　2log,　and　the　FC　concentration　in　BACK　effluent　was　31-504　MPN/L,　meeting　the　requirement　of　＇reclaimed　water　for　aesthetic　environment　use＇　with　FC　-1　(GB/T　18921-2019).　The　luminous　intensity　inhibition　rate　(IR)　of　O3　oxidized　effluent　increased,　with　an　average　value　of　11%,　while　the　IR　value　of　the　final　effluent　after　the　BACK　column　was　always　negative,　with　no　biotoxicity.　The　O3-BACK　can　effectively　reduce　pollutants　while　ensuring　the　water　safety　of　reclaimed　water,　providing　a　reliable　technical　option　for　wastewater　reclamation　and　reuse.　©　2022　Harbin　Institute　of　Technology.　All　rights　reserved.