Narrative:

Position was 65 NM west of ZZZ at FL340 when I received reports from the business class flight attendants of smoke and fumes in the cabin. The smoke/fumes were very noticeable though not visible. Passenger also noted the smoke/fumes. I received another call shortly thereafter from the 'a' flight attendant that she smelled smoke/fumes in the front of the cabin as well. With reports of smoke/fumes from both the front and aft sections of the cabin (smoke/fumes that were noticeable to the passenger as well); I elected to declare an emergency and divert into ZZZ since we were only 65 NM west at the time. Cockpit QRH procedures were followed. At no time were any indications of fire observed. Diversion and flaps 40 landing were uneventful although we touched down at 114.3 (300 pounds above maximum gross landing weight). In periodic conversations with the flight attendants during the diversion; the smoke/fumes were waning; then coming back again. During the final stages of the descent; the smell was dissipating and armed with this information I elected not to do an emergency evacuate/evacuation. ZZZ fire equipment was in place. We exited runway onto the high speed turnoff at gate X and came to a stop to have the fire trucks inspect us. Everything external to the aircraft appeared normal so we taxied to gate X with the fire trucks following us. All passenger were deplaned at the gate. When at the gate; contract maintenance opened the east&east compartment and immediately noticed a very distinct and strong odor that appeared to them to be electrical in nature. After all passenger were deplaned; the aircraft was completely pwred down. Fire personnel stayed on scene until the odor in the east&east compartment dissipated. All appropriate logbook entries were made as was notification to dispatch and my chief pilot.

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Original NASA ASRS Text

Title: A B737-300 IN CRUISE AT FL340 DECLARED AN EMER AND DIVERTED DUE TO RPTED SMOKE AND FUMES IN CABIN. NOTED BY CABIN ATTENDANTS AND PAX.

Narrative: POS WAS 65 NM W OF ZZZ AT FL340 WHEN I RECEIVED RPTS FROM THE BUSINESS CLASS FLT ATTENDANTS OF SMOKE AND FUMES IN THE CABIN. THE SMOKE/FUMES WERE VERY NOTICEABLE THOUGH NOT VISIBLE. PAX ALSO NOTED THE SMOKE/FUMES. I RECEIVED ANOTHER CALL SHORTLY THEREAFTER FROM THE 'A' FLT ATTENDANT THAT SHE SMELLED SMOKE/FUMES IN THE FRONT OF THE CABIN AS WELL. WITH RPTS OF SMOKE/FUMES FROM BOTH THE FRONT AND AFT SECTIONS OF THE CABIN (SMOKE/FUMES THAT WERE NOTICEABLE TO THE PAX AS WELL); I ELECTED TO DECLARE AN EMER AND DIVERT INTO ZZZ SINCE WE WERE ONLY 65 NM W AT THE TIME. COCKPIT QRH PROCS WERE FOLLOWED. AT NO TIME WERE ANY INDICATIONS OF FIRE OBSERVED. DIVERSION AND FLAPS 40 LNDG WERE UNEVENTFUL ALTHOUGH WE TOUCHED DOWN AT 114.3 (300 LBS ABOVE MAX GROSS LNDG WT). IN PERIODIC CONVERSATIONS WITH THE FLT ATTENDANTS DURING THE DIVERSION; THE SMOKE/FUMES WERE WANING; THEN COMING BACK AGAIN. DURING THE FINAL STAGES OF THE DSCNT; THE SMELL WAS DISSIPATING AND ARMED WITH THIS INFO I ELECTED NOT TO DO AN EMER EVAC. ZZZ FIRE EQUIP WAS IN PLACE. WE EXITED RWY ONTO THE HIGH SPD TURNOFF AT GATE X AND CAME TO A STOP TO HAVE THE FIRE TRUCKS INSPECT US. EVERYTHING EXTERNAL TO THE ACFT APPEARED NORMAL SO WE TAXIED TO GATE X WITH THE FIRE TRUCKS FOLLOWING US. ALL PAX WERE DEPLANED AT THE GATE. WHEN AT THE GATE; CONTRACT MAINT OPENED THE E&E COMPARTMENT AND IMMEDIATELY NOTICED A VERY DISTINCT AND STRONG ODOR THAT APPEARED TO THEM TO BE ELECTRICAL IN NATURE. AFTER ALL PAX WERE DEPLANED; THE ACFT WAS COMPLETELY PWRED DOWN. FIRE PERSONNEL STAYED ON SCENE UNTIL THE ODOR IN THE E&E COMPARTMENT DISSIPATED. ALL APPROPRIATE LOGBOOK ENTRIES WERE MADE AS WAS NOTIFICATION TO DISPATCH AND MY CHIEF PLT.

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.