Paul Simpson's side have now not won away from home for 16 games and their chances of promotion remain blighted by their inability to perform away from the New Meadow.
They gave Macc a head start in the 20th minute when left-back Shane Sherriff back-headed a speculative 40-yard free-kick from Lee Bell over his stranded keeper but inches under the bar.
The home side were then indebted to keeper Jonny Brain, who was vilified in midweek for a pantomime howler, only to respond with a breathtaking one-handed save to thwart a ten-yard bullet from Ben Davies.
Macclesfield should have extended their lead in the 40th minute when 20-year-old striker Gareth Evans dispossessed his former skipper Terry Dunfield to home in on goal.
But instead of rounding Luke Daniels he chose to shoot early, allowing the keeper to make a solid one-handed save.
Shrews' new striker Moses Ashikodi could have made a name for himself on debut with a shot from a narrow angle in the 51st minute, but it flew wide of the far post.
Moments later veteran striker Simon Yeo was crudely brought down by Ben Herd allowing Evans to fire home a powerful penalty for his ninth goal of the season.
Grant Holt nearly gave Shrewsbury a lifeline in the 86th minute when he deflected a Chris Humphrey drive inches past the post, but the game was sealed deep in injury time.
Jordan Hadfield picked out sub Nat Brown, who poked the ball past Daniels before slotting home his fifth of the season.
Shrewsbury's luck was out all afternoon and with virtually the last kick of the game top-scorer Holt was denied his 23rd goal of the season by a superb finger-tip save by Brain in front of the cheering home fans.