A municipal bridge with guardrails capable of ascending and descending comprises a bridge base (1) and a plurality of guardrail units (2) installed on the bridge base (1). Each guardrail unit (2) comprises two fixing sleeve stand columns (4), an upper cross beam (21) and a lower cross beam (22), wherein the two fixing sleeve stand columns (4) are fixed to the bridge base (1) in a bilaterally symmetrical mode, the upper cross beam (21) and the lower cross beam (22) stretch across and extend beyond the two fixing sleeve stand columns (4), the upper cross beam (21) and the lower cross beam (22) are provided with circuit devices and are fixedly connected through vertical railings (23), screw holes in thread fit with vertical studs (43) are formed in the two fixing sleeve stand columns (4), and the upper ends of the vertical studs (43) stretch into the upper cross beam (21) and are axially and fixedly connected with the upper cross beam (21) through upper thrust bearings (431) and lower thrust bearings (432).