Narrative:

Upon landing at ZZZ and taxiing to the gate; one of the company ramp personnel discovered a panel missing from the captain's side lower wing; just aft of the leading edge flaps. I went down to the ramp to take a look and verified that the panel and all but one of the fasteners were missing. The lone fastener was near the center of the aft set of fasteners. We grounded the aircraft and stepped to another. During my walkaround in ZZZ1; I cannot remember the panel to be missing. My standard flow walks me out to the wingtip along the aft end of the wing and back to the fuselage down the leading edge. I'm sure I would have seen a missing panel. No other damage was done on the aircraft upon my further inspection at ZZZ.

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Original NASA ASRS Text

Title: A B737-700 FLT CREW; AFTER TAXIING IN TO THE GATE AND WHILE PARKED; WAS ADVISED BY RAMP PERSON THAT A PANEL WAS MISSING ON THE LOWER L WING AFT OF THE LEADING EDGE DEVICES.

Narrative: UPON LNDG AT ZZZ AND TAXIING TO THE GATE; ONE OF THE COMPANY RAMP PERSONNEL DISCOVERED A PANEL MISSING FROM THE CAPT'S SIDE LOWER WING; JUST AFT OF THE LEADING EDGE FLAPS. I WENT DOWN TO THE RAMP TO TAKE A LOOK AND VERIFIED THAT THE PANEL AND ALL BUT ONE OF THE FASTENERS WERE MISSING. THE LONE FASTENER WAS NEAR THE CTR OF THE AFT SET OF FASTENERS. WE GNDED THE ACFT AND STEPPED TO ANOTHER. DURING MY WALKAROUND IN ZZZ1; I CANNOT REMEMBER THE PANEL TO BE MISSING. MY STANDARD FLOW WALKS ME OUT TO THE WINGTIP ALONG THE AFT END OF THE WING AND BACK TO THE FUSELAGE DOWN THE LEADING EDGE. I'M SURE I WOULD HAVE SEEN A MISSING PANEL. NO OTHER DAMAGE WAS DONE ON THE ACFT UPON MY FURTHER INSPECTION AT ZZZ.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.