Currently,　the　continued　high　prices　of　the　heavy　rare　earth　(HRE)　elements　Dy　and　Tb　are　prompting　an　exploration　of　the　development　of　HRE-free　high-performance　2:14:1-type　permanent　magnets.　In　this　paper,　a　high　maximum　energy　product　of　44.04　MGOe　at　room　temperature　(RT)　was　obtained　while　maintaining　a　coercivity　greater　than　20　kOe　in　HRE-free　Pr-Fe-B　sintered　magnets　through　microstructural　regulation,　which　reached　an　equivalent　to　the　commercially　45SH　level.　The　Pr-Fe-B　sintered　magnet　possesses　excellent　magnetic　properties　at　low　temperatures,　and　its　remanence　and　coercivity　increased　to　14.75　kG　and　75.01　kOe　at　-170　degrees　C,　respectively.　Microstructure　analysis　indicated　that　the　fine　and　uniform　columnar　crystals　in　the　strip-casting　(SC)　alloys　provided　conditions　for　the　preparation　of　fine-grained　jet　milling　(JM)　powders　and　sintered　magnets.　After　annealing,　the　continuous　grain　boundary　(GB)　layers　and　the　fine　grain　size　of　2.80　um　ensured　high　coercivity.　Meanwhile,　the　reduction　of　microcracking　at　the　GB　helps　densification　and　the　improvement　of　c-axis　alignment　ensured　high　remanence.　The　above　exploration　of　microstructural　regulation　throughout　the　metallurgical　process　can　provide　meaningful　guidance　for　the　development　of　HRE-free　Pr-Fe-B　sintered　magnets　with　high　performance.